And it happened at a 2008 Christmas party where Josh and Susan Powell attended.
There a Josh allegedly told a friend that he liked television crime shows. And he told the friend who wants to remain anonymous how to commit the perfect crime.
"He was basically telling me about how the best way to dispose of a body would be down a mine shaft like a vertical one,” says the friend. “It would be the best way of disposing one because they're so unstable."
He says Powell liked the idea of abandoned mines because no one goes near them.
A year after that conversation, Susan Powell went missing. No one could find her, so the friend went to police.
"It was like a year later,” the friend recalls. “All of a sudden Susan was missing it was like 'whoa are you kidding me? Did we really have this conversation a year ago?' and I had no idea. It was scary that I even had that conversation with him."
His account was found in the search warrant recently released by a Washington judge.
It was his tip to police that took them to Ely Nevada. And for three days police searched the abandoned mines outside Ely.
But in the end, there was no clue that got them closer to Susan.
And four years after that talk with Josh he wonders if the mine was really Susan's final resting place.
“I think it's a possibility,” he says. But to put it bluntly, I have a feeling he possibly did a handoff to his dad or something."