This could turn out to be one of the biggest criminal cases in US history.

It will turn out to be one of the most brilliant and insidious serial killers that we've ever seen in this country.

So uncooperative one's daughter has been abducted at gunpoint.

Hello and welcome to best case worst case. This is your host Jim Clemente, former New York City prosecutor retired FBI profiler and writer producer on CVS is criminal minds.

And with me today is.

Hi everybody. It's francey hates former state and federal prosecutor. How are you Jim?

I'm great. It's great to have you in studio with us today francey and we're both excited to have one of the favorite members of the ex g family with us today as our special guest.

Hi everyone. This is Bobby Cohn. Thank you for having me back you guys.

Well it's always great to have you Bobby and obviously we do so much work together.

It's so good to have you to do this episode of best case worst case because whenever I see you on TV or whenever you're here telling stories it's always very captivating and now we're going to be able to share some of that inside baseball with our listeners.

And I'm thrilled to have Bobby on just to give our listeners an example of behind police lines were really behind ex g lines last night Bobby was a guest on Fox News channel talking about something to do with the FBI.

And I didn't know he was on and my husband and I just turned it on and happened to hear Bobby calling into the particular show.

And I said Bobby and I said Bobby I see your on the phone on Fox News I know him.

Yeah that was one of those typical you know Jim and I deal with a lot of breaking news stuff when we get called and so I was booked on that show early in the day and then I was canceled on that same show.

And I was so excited to see him on the phone because I was so excited to see him on the phone because I was so excited to see him on the phone because they felt the story was not going to break and then I went to dinner with my wife on a Friday night and the story broke and I get a panic call from the producer can I do an interview or and I said well I'm sitting at dinner but she said well can we do pay via phone and so I stepped into a quiet all way much to my wife's your grand and I did a quick phone interview for Fox News on a breaking story with the FBI.

Well that's the life of people at XG that's the way we do it.

So today we want to give you an opportunity to talk about another one of your cases and I know that your cases typically are pretty grim but despite that they're very interesting and that you have helped resolve a number of very difficult cases across your career.

So we wanted to start with when in your career was this case.

This is actually late in my career. The case I'll talk about today is actually one of the last major cases that I worked on from a forensic standpoint.

This was in 2011 I believe so it was towards the very much towards the end of my career.

Got it. And what were you doing at the time that this case popped up in your life?

I was literally driving home on a Friday night in LA traffic Los Angeles is a famous traffic on a Friday night it's even worse.

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