New book “When the Night Comes Falling” deals with the murders at an Idaho college and the Bryan Kohberger case

MOSCOW, Idaho — A new book examines the University of Idaho murder case and investigates who may have been the target of the murders. Author Howard Blum’s book, “When the Night Comes Falling,” also describes what the surviving roommates are said to have done on the night of the brutal attack.

“My luck with this story was that I was there early,” Blum said. “I was out there before there was a suspect, so I was able to talk to a lot of law enforcement people while they were on the hunt.”

The book describes the months leading up to the murders of Xana Kernodle, her boyfriend Ethan Chapin, Madison Mogen and Kaylee Goncalves, as well as the terrible night in November 2022.

In his reporting, Blum concludes that Mogen was the target.

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“Authorities believe the suspect entered through the second floor sliding door of the house. As you enter the kitchen area, to the left is a bedroom where Dylan Mortenson was staying. To the right was Xana’s bedroom. If he was on a killing spree, it would have been natural – instinctive – to go to one of those doors. Instead, he goes up this narrow staircase and turns right into Maddie’s room. I believe Maddie was his target.”

Sources told both Blum and ABC News that the two surviving roommates used their cell phones to communicate during and after the murders.

“According to testimony before the grand jury, the two girls communicated and texted each other – not only after the murders, but even at times during them,” Blum said.

Blum also wrote about how concerned members of suspect Bryan Kohberger’s family were about his behavior leading up to his arrest.

Blum learned from family sources that Kohberger’s father, Michael, was nervous when he picked up his son from school that winter.

“He’s read the headlines. He knows that just 12 miles from his son’s house, four students were killed. He knows what a difficult son he has,” Blum said. “The Moscow police issued a BOLO (Be on the Lookout), a stop order on a car, a white Hyundai Elantra. He realizes that my son is driving a 2015 Hyundai Elantra.”

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According to Blum’s sources, Kohberger’s own sister later approached her father and expressed her suspicions about Bryan.

“She goes to Michael and says, ‘Dad, we actually have a real problem. I’m starting to think Bryan might be involved in these murders.’ And what does Michael do? He can’t deal with it. He just turns around and walks away,” Blum said.

Shortly thereafter, on December 30, 2022, Bryan was arrested at his parents’ home in the Poconos, Pennsylvania.

The Kohberger family has not commented on the allegations in Blum’s book.

SEE ALSO Kaylee Goncalves’ parents share new details about how their daughter killed in Idaho murders was found

Blum also described Kaylee’s father’s tireless search for answers. However, the Goncalves family told ABC News they “never spoke to Mr. Blum about the contents of his book.”

“When the Night Comes Falling” is released on Tuesday.