This is Hidden Killers with Tony Bruske. Here now, Tony Bruske.

Rob Reiner and his wife, Michelle, were found stabbed to death in the Brentwood home on Sunday afternoon.

Their son, Nick, who has struggled publicly with addiction and mental illness since he was a teenager, is now in custody, held without bail, charged with the murder.

The night before, all three were at Conan O'Brien's Christmas party.

Witnesses say Nick and Rob got into a very loud argument, loud enough that the room noticed.

Rob and Michelle left less than 24 hours later.

They were dead.

Now hindsight makes everything look a little more obvious,

but there's a real question here about warning signs.

What was visible, what got missed,

and what the people around Nick Reiner could have realistically done

or not at all because the system doesn't allow for it.

Robin Drake is a former FBI special agent,

Chief of the Counterintelligence Behavioral Analysis Program,

and just one of the best people I know at reading human behavior.

Robin, when you hear about the very public argument the night before a double homicide

at a, which should be a, I can't imagine the place that wouldn't be more fun and exciting

would be Conan O'Brien's Christmas party.

You know, I don't think it's a downer.

I think it's, you know, but for it to be something like this taking place there in front of all those people. I mean, this is like the stuff, you know, if you're going to have an argument with your kid, it's usually like they're an eight-year-old, not a 32-year-old and your 78-year-old father. What does that tell you about what's going on here?

It's the tip of an iceberg of a lot of leakage. You know, that is, and what we're seeing

there is massive leakage of what was really going on. And the hugest challenge of situation

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