Keith Morrison

As the school year came to an end in the spring of 2022, Maddie, with one more year to go, was making plans for life and work after college, as was Kaylee, who had just a semester before graduation. Zanna and her boyfriend, 20-year-old Ethan Chapin, had a little more time to figure out things. She was a junior, he a freshman.

As the school year came to an end in the spring of 2022, Maddie, with one more year to go, was making plans for life and work after college, as was Kaylee, who had just a semester before graduation. Zanna and her boyfriend, 20-year-old Ethan Chapin, had a little more time to figure out things. She was a junior, he a freshman.

And what none of them knew was that across the country, another student was making plans to continue his education. Brian Koberger had grown up in the Pocono Mountains of eastern Pennsylvania, an awkward kid who'd struggled with his weight, with girls. He'd written that he once looked in the mirror and saw a sickly, tired, useless and stupid man.

And what none of them knew was that across the country, another student was making plans to continue his education. Brian Koberger had grown up in the Pocono Mountains of eastern Pennsylvania, an awkward kid who'd struggled with his weight, with girls. He'd written that he once looked in the mirror and saw a sickly, tired, useless and stupid man.

But by 2022, he was 27, and Koberger had both kicked a heroin addiction and lost more than 100 pounds.

But by 2022, he was 27, and Koberger had both kicked a heroin addiction and lost more than 100 pounds.

This is Howard Bloom, award-winning investigative journalist and NBC News consultant. Bloom was on the ground in Idaho days after the murders and has written a book about the case, When the Night Comes Falling. He has studied Kohlberger intently.

This is Howard Bloom, award-winning investigative journalist and NBC News consultant. Bloom was on the ground in Idaho days after the murders and has written a book about the case, When the Night Comes Falling. He has studied Kohlberger intently.

And this new Brian had also found his calling, criminology. He'd received his undergrad and master's degrees at DeSales University, near his home in Pennsylvania.

And this new Brian had also found his calling, criminology. He'd received his undergrad and master's degrees at DeSales University, near his home in Pennsylvania.

And by the summer of 2022, he'd been accepted into the Ph.D. program at Washington State University in Pullman. Just a 15-minute drive across the state line from that house on King Road in Moscow.

And by the summer of 2022, he'd been accepted into the Ph.D. program at Washington State University in Pullman. Just a 15-minute drive across the state line from that house on King Road in Moscow.

What no one knew yet was that Brian Koberger, while finishing his master's degree, had gone on Amazon.com, as these documents in the possession of law enforcement and obtained by Dateline show, and he'd purchased a K-Bar U.S. Marine Corps knife A knife precisely like this one, nearly eight months before the murders.

What no one knew yet was that Brian Koberger, while finishing his master's degree, had gone on Amazon.com, as these documents in the possession of law enforcement and obtained by Dateline show, and he'd purchased a K-Bar U.S. Marine Corps knife A knife precisely like this one, nearly eight months before the murders.

Then on June 25, 2022, he used his phone to take this picture of his car, a 2015 white Hyundai Elantra, just as he pulled away from his family home in Albrightville, Pennsylvania, headed toward Washington State and the fates that awaited them all.

Then on June 25, 2022, he used his phone to take this picture of his car, a 2015 white Hyundai Elantra, just as he pulled away from his family home in Albrightville, Pennsylvania, headed toward Washington State and the fates that awaited them all.

Cinematic, yet very raw and real. And reported here for the first time, the phone calls Koberger made in the hours after the murders.

Cinematic, yet very raw and real. And reported here for the first time, the phone calls Koberger made in the hours after the murders.

The text message to a woman who met Koberger at a party before the murders.

The text message to a woman who met Koberger at a party before the murders.