This guy was like American psycho. I can do something even more important, something larger. I can become a serial killer and get away with it. I have never seen from any case I've covered someone so completely devoid of anything internal.

This is the Idaho Massacre, a production of KT Studios and IHeart Radio.

Season 3, Episode 5, Strange Behavior.

I'm Courtney Armstrong, a producer at KT Studios with Stephanie Leidegger and Gabriel Castillo.

Over 100 documents have been released by the Moscow Police Department, and another 550 by the Idaho State Police. Together, they don't just fill in the blanks, they reveal an even clearer and at times far more troubling picture of this case.

Crime analyst Body Moving takes us deep inside the files that focus specifically on Brian

Coburger's behavior. What his colleagues noticed, the patterns that emerged, and the red

flags that may have been hiding in plain sight. Then, behavioral analyst Robin Dreak helps us connect the dots, breaking down what these

documents reveal about Koberger's mindset, his decision-making, and the strange behaviors

that led up to the murders.

You'll hear Robin's theory on motive why he thinks this seemingly promising PhD student took such a dark turn.

But first, let's start with Body Move-in and Stephanie Lidecker as they guide us through some of the most revealing files yet.

All of these findings and files are coming out publicly, and we can't get through them fast enough.

We're eating them up as quickly as possible.

But it shows a lot into his brain space while getting his PhD.

He's described by many as creepy, socially awkward, and domineering.

He frequently stared intensely at people. One woman counted

nine times during a class. She saw him staring at her intensely, like creepy, scary.

Like without a blink. You know how sometimes you might just be gazing in a direction and you

happen to be looking at a person and it's so embarrassing. You're like,

I swear I'm not overly staring. But in this case, this was a repeat pattern. And he wouldn't

really blink. He would just be so intensely staring. He exhibited this macho or puffed up demeanor.

...