Tonight on Dateline.
My mom called me.
There's a fire at the house, there's a fire at the house.
I just kept praying, please let her be okay.
It was classified as a homicide.
Before she died, a mystery man popped up at the house, looking over the fence, looking in the backyard.
There were some strange phone calls that were coming in.
She was worried and scared.
We decided to do an undercover operation.
Did you tell him you had nothing to do with this whatsoever?
So I asked him, did you kill her?
He was living a double life.
She knew nothing.
He gets on that flight.
We have no way to stop him.
He waited for darkness so that he could light the fire.
The killer or killers are out there.
What if we're next?
A young mother is killed in a mysterious fire, and it would take some creative police work to solve this one.
I'm Lester Holt, and this is Dateline.
Here's Andrea Canning with Fire and Ice.
Do you require police fire ambulance?
Hello, there's a fire.
The first call came in at 7.50 p.m.
Okay, where do you see the fire?
In the garage.
The flame, yes.
Very bad, very bad.
It was September 15th, 2014, a rainy evening in the lakeside city of Pickering, a suburb of Toronto.
Anna Connelly's husband had just left to take their dog for a walk.
What happened next is still hard for her to talk about.
And then he turned around and he says, Carm's house on fire.
It was coming out from the garage.
Carm was Carmella Knight, Anna's neighbor.
When Anna stepped outside, the first fire truck was already on the scene.
More were on the way.
And the fire just kept going.
It was so bad, the fire.
And you couldn't, you couldn't do anything.
Carmela lived with her husband David and two young sons.
Anna had no idea if any of them were in the house.
She felt so helpless.
Carmela was one of her best friends.
If you ever met Carm, instantly you become friends with her.
Now Anna couldn't reach Carmela on her cell phone.
So she called Carmela's mom, Franka, hoping they were together.
My phone rang, and it was Hannah.
And she was screaming on the phone. and saying, is Carm with you?
And I said, no, what's wrong?
What's wrong?
When you realized that they were not together, did your heart just sink?
Yes.
Yes.
I went straight over to the house.
And what is that drive like with all the unknowns?
It was just awful.
I just kept praying.
Just got to pray, please let her be OK.
Please let her be OK.
When you arrive at the house, what do you see?
There was still a bit of fire on the top of the garage.
And I just ran.
The door was open.
I felt like something, a body, which I thought was a body.
But two firemen and two police officers came and they stopped me.
Carmela's sister Nancy arrived soon after.
What do you see?
Fire trucks and all the neighbors.
Everyone was, it was just very busy.
And like my mom just kept saying something happened to her.
And I just said, no, she's fine.
She's fine.
Nancy frantically tried to reach Carmela's husband.
I tried calling Dave numerous times and I wanted to make sure the boys were okay and if Karma's okay and if he had spoken to her.
And was he answering the phone?
No.
An officer asked Nancy and her mom to go to the police station.
They knew it wasn't a good sign, but Nancy refused to give up hope.
Everything's fine.
Don't worry.
When we get to the police station, everyone's going to explain.
It's going to be okay.
You're still thinking she's alive?
Yeah.
At the station, they learned David and the boys were safe.
They'd been at hockey practice.
While that was a huge relief, what police said next was hard to process.
They confirmed what Franka thought she'd seen in the garage, did say that they found a body, but I was still hopeful.
But in the back of your mind, you're like, she's not answering her phone.
And it just makes you feel sick to your stomach.
David and the boys showed up at the station.
He left them in the car with his father and went in to speak with police.
A detective told him they'd found a body and that it might be his wife's.
Okay?
We don't know that at this point, but that's the reason that you're here.
David immediately worried about his sons.
Yeah, that's where I say it.
We'll do this step by step, all right?
No one wanted to believe their beloved Carm was gone, a woman who meant the world to so many people.
She just had this sense of calmness to her that just put me at ease.
While Nancy held tight to the hope that Carmela was still alive, law enforcement got to work.
Durham Regional Police Detectives Diane Jennings and Leon Lynch were assigned the case.
What condition was the body in?
What could they tell from initial assessment?
It was a badly charred body and they could not recognize who the person would be.
It wasn't until detectives heard from the forensic pathologist that they confirmed the victim was 39-year-old Carmela Knight.
How was she identified?
By her dental records.
And the pathologist told them something else about Carmela's body.
They discovered that she had a tourniquet around her arm and a syringe with her body.
This is drug paraphernalia.
Yes.
Yes.
Surprising?
Absolutely.
This is a hockey mom, a suburban mom.
Exactly.
It was a puzzling clue in what would turn out to be a complicated case.
Could you just tell, just from all your years of experience, that this was not going to be easy?
Yes.
That's fair, yes.
They had no idea solving this mystery would become a battle of wits and a race against time.
When we come back, delivering the heartbreaking news.
I just didn't want it to be true.
And a disturbing discovery.
Carmela was dead at the time of the fire.
So she died before the fire.
She did.
The next day, the house on Pebblestone Crescent was still smoldering when police broke the news to Franca.
The body found in the garage was her daughter Carmela's.
Her cause of death was still unknown.
They just said it could be an accident.
She could have died in the fire.
We don't know.
Carmela's sister Nancy thought about how Carmela sometimes smoked in the garage.
Their dirt bikes are in there, so we're like, maybe something happened with that.
The gasoline and stuff, like, who knows, right?
So an accident may be.
But when police brought up the possibility of a drug overdose, Did you believe that she could do drugs?
No, God, no.
She didn't even drink.
She had an occasional glass of wine.
Her youngest son Dylan, remembers his father breaking the news of his mother's death to him and his brother.
Our dad sat in front of us, and he couldn't even tell us.
He sat there crying.
At first, I didn't want to believe it.
I really didn't.
I didn't think it was true.
I just didn't want it to be true.
Nancy was also finding it hard to believe.
She had just been with Carmela.
She was happy.
They'd been planning Nancy's wedding.
Now she was attending her sister's funeral.
That church held 600 seats.
All the seats were full.
There was people all along the walls, in the back.
It really shows you.
How special she was.
She was very special.
Yeah.
A few days later, the pathologist told detectives how Carmela died.
It was confirmed that it was in fact a homicide.
She'd been murdered.
Detectives Jennings and Lynch poured over the report.
It was gruesome, but it was the evidence they needed to kick off their investigation.
They knew that Carmela was dead at the time of the fire.
So she died before the fire?
She did.
They also told us that she died of blunt force trauma.
She had facial injuries and she died of a neck compression.
They could tell all of this even with the badly burned body.
Right, they could.
The fire just destroys the outside of the body and all the damage that happened prior to death is still evident underneath the skin.
Of course, in a case like this, police usually look at the husband first.
So they learned what they could about David Knight.
He worked in construction as a project manager.
He and Carmela owned that nice four-bedroom house in Pickering.
And they had a second home in Indian Rocks Beach, Florida.
Why don't you take a deep breath and try and relax?
In his police interview on the night of the fire, David took investigators through his day.
Where does David say he was during the time of the fire? at the hockey rink with his boys.
He left the house around 330, went to McDonald's and then went to the ice rink in Toronto and had a practice.
From 6.30 till 8 o'clock.
This is something that is easily verifiable.
Definitely, yes.
He was at the hockey rink during the fire.
Many witnesses saw him there on the ice.
And we have video surveillance showing him skating around on the ice during that timeline.
He also told the detective that while he and Carmela lived in the house together, they were sleeping in separate bedrooms.
Their marriage was ending after 15 years.
He's talking about their relationship.
It was an amicable separation in that he loved Carm.
And his reaction to the news that night seemed genuine.
The detective thought he was emotional when he was told.
Acting the way one would expect when they've just received news like this?
Yes.
Yes.
And besides, his alibi was airtight.
So detectives wondered, if Carmela's husband wasn't the killer, who was?
It was time to find out more about her from other people in her life.
We learned that she was very involved with her boys.
Nobody could say a bad thing about Carmela.
There was nothing negative whatsoever in any interview.
Tara Cochimilio was one of the people who'd spoken to police.
She and Carmela were friends from college.
We had a lot in common and we became the best of friends.
What do you think it was about you two that eventually you just totally hit it off?
To be honest, we both like to party.
And have a good time.
Sounds familiar.
Yeah.
She was a sweetheart.
She had a heart of gold and she was so genuine.
Tarot says they had similar dreams for the future.
I knew that we both really wanted families and children.
She remembers Carmela first met her future husband at a nightclub.
She said she met somebody and that he had sent her flowers.
That doesn't always happen after you meet someone at a club.
No, it doesn't.
Somebody that's going to send you flowers right away to show that they were so happy to meet you is usually a good sign.
It was a very good sign.
After a quick courtship, Carmela and David got engaged on Christmas Day.
What were the big plans?
Did she say right away?
Did she know what she wanted?
You know, a big Italian wedding.
Was she really happy on her wedding day?
She was very happy.
She was a beautiful bride.
Not too long after that, Carmela and David welcomed their first son.
We were all so excited to meet him.
Could you just see it in her eyes, the joy and the love that she had for her firstborn?
Yes.
She was thrilled to be a mom.
Three years later, Dylan was born.
What did you love about your mom?
Just, I guess, the way she cared about me and made sure that I knew I was loved.
She was an official hockey mom?
Yeah, she definitely was.
She was always out there screaming and shouting.
No one ever said anything to detectives about Carmela using drugs.
So a few weeks later, when they got her toxicology report, the results didn't surprise them.
No drugs in her system.
Her tox was negative.
What did that tell you about the scene with the drug paraphernalia?
Did it suggest to you that the scene had been staged?
When we pieced everything together, it certainly did.
Another clue came from the home security system.
Interior door sensors had been tripped.
It showed that somebody was in the house after David and the children left for hockey.
They knew David and the boys left around 3.30 that afternoon.
Carmela came home from work around 5.
So we had some unexplained doors opening and closing.
Somebody was going into different areas of the house.
Who was that somebody?
Franca recalled something her daughter had said.
Carmela had told you a story about someone approaching her, a man from a black SUV.
She was in the backyard.
Dave had taken the boys dirt biking.
A man looked over the fence and asked for Dave, and she said, Dave's not here.
And he left, and then she ran to the front and saw this man getting into the black SUV and took off.
Did she know who it was?
No.
So this is a...
A mystery man that's showing up at her house.
This really thickens the plot.
Yes.
Coming up, Carmela's sister-in-law visits police and drops a bombshell.
He just said, I know who, what, when, where, and how.
With a phone call, I could have stopped this, and I have to live with it for the rest of my life.
And he burst into tears.
When Dateline continues.
Police were pursuing a new lead in the Carmela Knight murder investigation.
Her mother had told them about a mysterious man in a black SUV who surprised Carmela in her backyard.
She was scared.
She didn't know who he was.
Franca said Carmela told her husband David about the unexpected visitor.
She told her, this guy came looking for you, Dave, what's going on?
Oh, nothing, nothing, nothing, right?
But then he puts the alarm on that night and he's like really paranoid, like scared.
Jumpy?
Yeah, very, very jumpy, she said.
But as detectives were trying to figure out who the man was, somebody else popped up on their radar.
Heather Knight, Carmella's sister-in-law.
She came into the police station and gave a statement.
Heather was married to David Knight's brother, Matt.
And when she heard Carmela had been murdered, a sinking feeling crept in about her own husband.
First, she told the detectives that Matt had abruptly left Canada.
And this is very quickly, very soon after Carmela's death.
Two days later.
He's off to Florida.
It wasn't just that Matt left.
She said he acted like he was never coming back.
He left a key to their house on the table when he left.
But what bothered Heather the most was the last thing Matt said before he got on the plane.
He just said, I know who, what, when, where and how.
With a phone call, I could have stopped this and I have to live with it for the rest of my life.
And he burst into tears.
Now the detectives were really listening.
He says maybe 20, 30 years down the road when we're on a beach, somewhere or something.
I'll fill you in on everything.
But I don't want to tell you everything because I don't want you to be in that position.
Heather went on to tell them that on the night of the fire, as soon as Matt heard about it, he rushed out of the house.
She assumed he went to go see his brother, but then she got a phone call.
From David Knight saying, where's Matthew?
And she thought, I thought he was with you.
And then she later learns that in fact he was with Graham.
Graham McDonald, a name that was new to investigators.
Graham McDonald was a friend of her husband, and Graham and Matthew had worked together at a company called Hot Sets in Toronto.
So he was just a family friend.
Graham, a handyman, was also friends with Matt's brother David.
In fact, David hired him to spruce up the house on Pebblestone Crescent.
So why had Matt rushed out to see Graham in the middle of a family crisis and not his brother?
A team of investigators left Canada for sunny Florida to ask Matt.
They went to his house.
They left a business card.
They were able to speak to him on the phone, and he refused to speak to them.
He said that Heather's a liar.
She's just trying to get him into trouble and that he has no intentions on ever coming back to Canada.
With no jurisdiction in the US or any evidence to press Matt further.
Investigators came home empty-handed.
What's more, they knew that Matt, like his brother David, had an alibi for the day Carmela died.
He was with Heather.
She made it very clear that him and her were together that entire day.
He did not leave her side.
And there's no way that he could have done it.
They had struck out with Matt, so they brought Graham McDonald into the station to ask him where he was the day of the fire.
He told us that he went to visit his grandmother, but his grandmother wasn't home.
He also told us that he took the GO train back from Toronto out to Pickering and then walked from Pickering to Moody's Motel.
But then they did some digging.
We got video surveillance from his grandmother's apartment and Graham did not appear on the surveillance video.
Was that fishy that he told you he went there and then he's not on the surveillance video?
It is fishy.
We looked at all the GO train surveillance.
Graham McDonald was not on the GO train.
Police started to wonder if Graham might have had a reason to want Carmela dead.
Did you think that maybe Graham McDonald had some type of an obsession with Carmela, that possibly when he was doing renovations he got fixated on her?
Definitely the way his story wasn't panning out.
And if he had some type of relationship with her and it didn't go well...
After talking to friends and family, the scorned lover theory didn't go anywhere.
But after catching him in those lies, they needed to talk to Graham again.
So they called him back for a second interview.
Graham maintained he was in Toronto that day, but his memory of it was hazy and there was a good reason for that.
What do you mean you weren't all there?
He was using drugs that day and his recollections all over the map and I jumbled because of that.
He doesn't really remember where he was.
When pressed by the investigators, Graham got upset and wanted to end the interview.
I don't want to do this anymore.
I'm going to stop.
You guys do what you need to do.
Okay, but no.
Graham, listen.
I don't know what to do here.
He became a person of interest that needed a lot more investigating.
And he wasn't the only one.
Graham had led them to a possible new suspect.
Somebody is not telling the truth here.
There's some gaps in the story, absolutely.
Coming up...
They meet up with him in the parking lot.
They try to engage him in conversation and he just wouldn't stop, wouldn't speak to them.
A suddenly silent husband living a double life.
There was naked photos of this girl and she was kissing him on the cheek.
With each passing month, Carmela's mother Franca grew more impatient with the investigation.
I phoned John, one of the detectives two, three times a day, calling like what's going on?
What's going on.
And they kept saying, you know, we're working on it, we're working on it, you know?
She had no idea about the detective work unfolding behind the scenes.
During Graham McDonald's first police interview, he'd revealed something that sent the investigation in a whole new direction.
What does he tell you?
He tells us that he was with David Knight the day of the murder.
A red flag.
They'd spoken at length to Carmela's husband the night of the fire and he told them he was at the hockey arena that evening.
There was security camera footage that proved it, but according to Graham, David wasn't telling the whole story.
David Knight never mentioned being with anybody that day.
And now Graham McDonald's telling us that he was with David and that they went to Toronto.
Detectives were now taking a hard look at David Knight and some of his behavior after the fire was raising eyebrows.
Carmela's friend Tara says he didn't attend Carmela's funeral.
It was awful to think that your wife could die so tragically.
And even if you were separated, that you wouldn't come to pay your respects.
Even worse, she says he didn't let their young sons go.
They weren't at their own mother's funeral?
Oh my gosh.
But Carmela's mom wasn't surprised.
She knew the divorce proceedings hadn't been going as smoothly as David let on.
In fact, she says it got ugly.
David was telling lies about Carmela all over town before and after her death.
Dave told all the hockey parents that she was a gambler, that she had a boyfriend, that she was taking drugs.
Do you think the parents were buying this?
No, no, they weren't.
Carmela had complaints about David, too.
Tara told investigators that Carmela had long suspected he was unfaithful.
He'd stay late at work, come home without his ring, travel more and more.
I think there was some receipts.
There were some strange phone calls that were coming in.
And a year and a half before her murder, undeniable proof.
Carmela found a thumb drive in David's car filled with racy photos.
She confided in her sister Nancy.
So there was naked photos of this girl and there was a picture of Dave and her and she was kissing him on the cheek.
So there was no getting around this.
No.
This was, yeah.
Adultery.
Yeah, exactly.
Nancy said David finally admitted he had a girlfriend who lived near that second house in Florida.
David promised Carmela he'd stop seeing her immediately, and they went to marriage counseling.
But months later, she discovered the affair was still going strong.
Then she just decided, she said, enough's enough, I can't do this anymore, and told him.
How did he react?
As she was telling him, he was begging for her to come back.
And she said, no, I can't do this anymore, you've had chances, and that's it.
Police wanted to hear more from David, but when a team of investigators went to speak with him, he ignored them.
They meet up with him in the parking lot.
They try to engage him in conversation and he just keeps walking and wouldn't stop, wouldn't speak to them.
After that, David lawyered up, so investigators turned their focus toward the girlfriend.
While they'd been in Florida trying to speak to David's brother, they'd paid her a visit.
She says that she was under the impression that David had been divorced for six years, that they met in a bar about a year and a half prior.
She knew everything about his Florida life.
It just seems that she didn't know anything about his Pickering life.
David Knight was living a double life.
Yes.
They learned his plan was to set up a construction business in Florida and move there permanently.
But he ran into serious money problems in the months before Carmela's death.
We're learning that Carmela was in financial dire and that he wasn't paying the mortgage or helping her out with the boys.
And she filed an emergency motion for custody of the children.
And that hearing was supposed to be heard on the Thursday.
After her murder.
That was just three days later.
Yes.
Investigators wondered if David had found a solution to his financial problems.
He had taken out two life insurance policies on Carmela, totaling $850,000.
David had a lot to gain from Carmela's life insurance policy.
He did, and he needed that money.
The business deal was closing September 25th, which again was right after her murder.
Time was running out for him that he needed to make this happen.
Police were now convinced that David Knight was somehow involved in his wife's murder, but they didn't have any real evidence.
They needed more time to verify if David really was with Graham the day Carmela was murdered, before he was seen at the hockey rink.
But time was running out.
David was about to bolt.
Once he lawyered up, detectives got a court order to tap his phone and they learned he was planning to move to the Sunshine State.
And what does that mean for your investigation?
It would have been very problematic to investigate him while he's in Florida and might have meant that our investigation was over.
Detectives had seized David's passport earlier in the investigation, but now they learned he had found a way to outsmart them by going to the government agency that issues passports.
He then falsified a document saying that he lost his gym bag and lost his passport.
Passport Canada reissued him a new passport.
A new passport meant David Knight could slip through their fingers for good.
This was a race against time.
It was.
It was.
Coming up, David had an ace up his sleeve, a private jet, and an unwitting accomplice.
You were about to transport an alleged killer to Florida.
Exactly.
He gets on that flight.
We have no way to stop him.
When Dateline continues...
Three months after Carmela Knight had been murdered, detectives learned her husband David, a possible suspect was about to hop on a private jet headed for Florida.
He planned on never returning to Canada again.
Once he moved, that was it.
The wiretap on David's phone was paying off.
We were able to listen to his plans, namely purchasing a house, enrolling the boys in school, and what his future plan was in Florida.
This was bad news for detectives.
They'd been building a case against him, but they still didn't have enough evidence for an arrest.
It was very, very tense because we thought he was going to be able to get on that jet.
Pilot Bassam Al Sarraj remembers the request coming in from a customer looking to fly private to Florida immediately.
It was actually an evening around 8 o'clock at night and I said oh, this guy's really looking to go somewhere.
So Bassam called up the customer.
It was David Knight.
I said, hey, this is the deal.
We actually found a plane that just happens to be going to Florida.
David wired $15,000 and the trip was set for the next morning.
Are you on pins and needles?
Yes.
He gets on that flight.
We have no way to stop him.
So detectives had an idea.
Remember, David had lied and gotten himself a new passport.
Police made a plan to confiscate it before he got on the plane.
So this confiscation of his passport is based less on the murder investigation and more on him falsifying passport documents.
Right.
But detectives didn't have much time.
They contacted police near the airport and asked them to send officers to intercept David.
Bassam.
The pilot remembers David arriving for his flight just as the plane was fueled and ready to go.
He shows up.
He's got his dog.
He's got his luggage.
We put the luggage in the plane.
Does David Knight have any idea that the police are in there?
No, no idea.
And that's when the police stepped in.
Police officer comes out and says, I'm seizing your passport on behalf of Government of Canada.
Oh my gosh, what did David Knight say?
He freaked out.
No passport, no chance of escaping to the United States.
You were about to transport an alleged killer to Florida.
Exactly.
Police let David go, but he had to know detectives were zeroing in on him.
And in fact, they were making progress in other parts of the case.
They had identified the mystery man in the black SUV.
It was David's ex-business partner.
This business partner must have been angry.
He was, yes.
Angry yes, but the more they investigated, the less they thought he had anything to do with Carmela's murder.
They believed he showed up in the backyard to confront David, not scare Carmela.
That left just David, Matt, and Graham, and they weren't talking.
So detectives knew they needed to do something big.
We decided to do an undercover operation with Graham McDonald.
Graham is the target?
Yes.
The plan was for an undercover officer to befriend Graham, for them to become friendly, for them to build some rapport.
You know, play pool together and that sort of thing.
That's eventually what ended up happening.
They became friends.
Graham right away told him that, look, the police are looking at me for this murder.
The undercover officer said he knew someone who could help him.
He introduced Graham to Uncle Dan, another undercover officer who was posing as a man who had a history of fixing people's troubles with the law.
Uncle Dan agreed to speak with us, as long as we didn't show his face.
You're not friends with Graham McDonald.
You don't want to be friends with him.
But yet...
You have to convince him of that.
It's done through different scenarios throughout this whole operation, just to show that you know I was somebody trustworthy.
Undercover officer, Uncle Dan invited Graham and his friend out for a day of ice fishing on Lake Simcoe.
But something conveniently happened on the way to the lake.
While they were on their way to the hut, they were pulled over by the police for a traffic stop.
The police officer ran both of their names through the police system and Graham McDonald had a return of being a subject in a homicide.
They hoped mentioning Carmela's murder might get Graham out of his comfort zone.
As a result of that traffic stop, Graham McDonald appeared to be very rattled by the fact that the police had named him what he thought was a suspect.
Eventually, the police let them get on their way.
Everything was now riding on this meeting in the ice fishing hut.
Could Uncle Dan get Graham to take the bait?
So when I came into the hut, Lorraine was sitting in the corner and I said to him I heard you have a problem.
The problem we're running into now, they're starting to throw mining around.
I don't know if they're using it as an escape mode or whatever the case may be.
So can you tell them you've had nothing to do with this whatsoever?
Are you telling you that?
I can't.
So I asked him, did you kill her?
Coming up... I could tell that he kind of had tears in his eyes.
Something was really bothering him and he wanted to talk.
Can Uncle Dan reel in a suspected killer?
I was shocked.
I didn't expect that to happen.
In that bitterly cold ice fishing hut, Graham McDonald was unknowingly face-to-face with an undercover officer.
Detective Jennings waited nearby with bated breath.
I was in a vehicle on the shore just over there off to a parking lot listening live.
I asked him, did you kill her?
And he nodded yes.
I was shocked.
I didn't expect that to happen.
And it was a huge breakthrough.
They finally had the first piece of the puzzle.
But detectives believed Graham hadn't acted alone and were certain his confession wasn't the whole story.
Uncle Dan needed more, but he was careful not to push Graham.
Instead, he ended the meeting.
A week later, Uncle Dan invited Graham to his office.
Investigators had come up with a clever way to get Graham to give a full confession.
We developed a scenario where I said, I think I might be able to fix this problem for you.
And I said, I have a good friend of mine who's dying of cancer and doesn't have long to live.
He will take the rap for you.
He will confess to it.
But you need to ensure that his children will be looked after.
$10,000 trust funds for each child.
And he'll do this for you.
And, like a Hollywood movie, they used makeup to disguise an undercover officer named James to play the part of the dying man.
When he showed up at the office in a wheelchair, they told Graham if James was taking the fall for the murder.
He needed to know every last detail.
I had him go through his involvement, how it was planned, how it was executed.
And that's when Graham laid it all out.
And not only his involvement, but David Knight's too.
He said David had hired him to kill Carmela.
He said David wanted his wife gone.
Graham did say there's a lot of planning.
Graham told them.
On the day of the murder, David went to fill up gas cans to be used to set the fire.
He said David later took him to the house and let him in.
He then hid in the bathroom waiting for Carmela to come home.
She came in through the garage and he attacked her from behind.
And she fought for her life.
He raced around the kitchen island.
He finally got her down on the ground and strangled her.
He said he tried to make it look like Carmela had overdosed.
He placed the tourniquet on Carmela's body and tried to inject her with cocaine, left the syringe in her arm.
And then what happened next?
Then he dragged her to the garage and put her face down in the garage.
And he waited.
He waited for darkness. so that he could light the fire.
This was all about money for Graham?
Well, he was promised $100,000 from David Knight and a life in Florida.
Now, investigators had to be sure Graham's confession checked out.
They easily found the video of David at the gas station filling the gas cans.
And they discovered another video that proved Graham was with David on the day of the murder.
That's him in the passenger seat.
Graham also told Uncle Dan that he and David bought burner phones.
So detectives took another look at the video supporting David Knight's alibi.
This is David Knight at the ice hockey rink the night of the murder.
That's correct.
You can see he's got his one hand up and he's speaking on a cell phone. while he's skating around.
That's right.
The time stamps on the calls there are actually right after Carmela's murder.
Phone records proved it was Graham on the line.
Now, there was just one last box to check.
In order to arrest David, investigators needed proof he paid Graham for the murder.
As luck would have it, David hadn't given him a dime yet.
This was their opening.
The undercovers told Graham that you know you were promised 100000 and he hasn't paid you anything, so you need to go collect.
Detectives put a tail on David and found his favorite watering hole.
Graham's friends, the undercover officers, convinced him to pay David a surprise visit at the bar.
When he did, other undercover officers were scattered around inside.
And unbeknownst to David, and even to Graham, Graham was recording it all.
We did provide him with something that he wasn't aware of that was actually a recording device.
And there were also other recording devices in the area.
So you're about to capture this whole conversation on tape.
Hopefully, yes.
What happens when Graham approaches him?
They talk.
He was quite shocked to see Graham walk back into his life again.
And I think his first thing was like, what are you doing here?
During a brief conversation, Graham told David all about Uncle Dan and the plan to have a dying man take the fall for the murder.
David bought it hook, line, and sinker and told Graham to come back a few days later.
They made an arrangement to meet the following Thursday, and that was when David Knight paid him 5000.
I'll watch somebody else count this.
Nearly six months after Carmela was murdered, investigators had their men.
David Knight, Graham McDonald, and Matthew Knight were all arrested for the murder plot.
Nancy, who had long suspected David played a role in Carmela's murder, felt vindicated.
Did it give you some relief even for just a moment after everything you'd been through?
Oh yeah, definitely it did.
Like a hurrah, kind of like, you know, finally they caught him.
After a four-month trial, David Knight was convicted of first-degree murder, conspiracy to commit murder and arson.
Graham McDonald was convicted of the same crimes.
Each was sentenced to life in prison with a chance of parole after 25 years.
Matthew Knight pleaded guilty to accessory after the fact to murder.
He spent a year behind bars.
It was less time than detectives had hoped for.
They did, however, think David Knight got what he deserved.
Instead of living his new life in Florida, he's in an 8x10 cell.
He is.
That's where he should be.
Franka couldn't agree more.
I want him to suffer, and every day of his suffering, I want him.
I wanted to see Carm's eyes, you know, and think of what he did and how he destroyed the family.
I didn't want to believe it, and I believed him for so long.
She just came to the realization that he ruined my childhood and he put me in a place that I don't know if I'll ever get out of.
It must just feel like a bad dream sometimes.
Sometimes, yeah, I wish it was.
But unfortunately it's not.
Dylan now lives with his Aunt Nancy.
I'm glad that you had a soft landing with your aunt and uncle and that you found a home where you have two little cousins that you're like a big brother to now.
Yeah, pretty much.
Yeah, they make me happy.
They definitely bring me joy in life.
Nancy's friends gifted her a necklace in her sister's handwriting.
A keepsake, she says, is so meaningful that she decided to get one for her mom, too.
They wear them often, keeping Carmela close to their hearts.
And they gather every year to celebrate Carmela's birthday.
They make a home-cooked meal together.
Franca still sees her daughter in her grandson's.
Do you think Carmela lives on through her boys?
She does.
Dylan looks exactly like her.
Is the future bright for them?
I hope so.
I hope so.
They have a lot of karma, thank God.
That's all for now.
I'm Lester Holt.
Thanks for joining us.
