Tonight on Dateline. I was a victim of lies and manipulation for far too long. It was hard. It was really hard. I'm not a victim. I'm a survivor.

As we go in the front door, John is lying on his sofa, gun shop room to the forehead.

He was a firefighter.

He had everything in the world going for him.

They took my pride and joy from me.

My son gets murdered. For what? The person that called was Jennifer McKay. She had been dating him John.

Turns out that she had a previous relationship.

I thought he was a debaured.

Infidelity married people.

This could be a classic ingredient in a homicide.

Correct.

I just said, like, stay away from my husband.

My life has already been flips upside down.

You got an absolute prime piece of evidence.

It's surveillance footage from next door.

This camera captured the intruder, the killer.

It was just unfathomable.

Jealousy and lies, adultery and obsession.

Who shot the firefighter? I'm Lester Holmes. and Here's Dennis Murphy with The Killer on Camera 4. Amazing Grace.

The bagpipers mournful lament for fallen firefighters.

It's the way a brotherhood says farewell to one of its own.

But this firefighter didn't fall amid the smoke and ashes.

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