COLUMBUS, Ohio (WCMH) — A memoir by a local former forensic psychologist unfolds with one of the city’s most disturbing unsolved double homicides that became known as “The Riverside Murders.”

The book, “That Beast Was Not Me: One Forensic Psychologist, Five Decades of Conversations with Killers,” by Columbus author Jeffrey Smalldon, chronicles his years of dealing with some of the most infamous criminals in U.S. history. Through the pages, Smalldon reveals his interactions with notorious felons such as Charles Manson, Ted Bundy, John Wayne Gacy, Lynette Squeaky Fromme, Susan Atkins and others.

However, Smalldon’s work goes beyond the most sensational names, detailing the brutal killings of his coworkers Patricia Matix and Joyce McFadden at Riverside Methodist Hospital in Columbus. In the first chapter, he describes how the mysterious deaths and chilling aftermath prompted him to leave his career in hospital administration and earn a PhD in psychology from Ohio State, eventually becoming a forensic psychologist.

Smalldon writes that the Dec. 30, 1983, murders were a “baffling double homicide” that took place just after he turned 30 while working as an “up-and-coming junior administrator” at Riverside. He cites the experience as “the bridge” from his “college-era attempts to penetrate the thick fog surrounding the Manson case” to his path in forensic psychology that became his life’s work.

“I’ve provided consultation on close to 300 death penalty cases and evaluated more than 1,000 murderers altogether: serial, mass, spree, all kinds,” Smalldon notes in his book.

In an email to NBC4, Smalldon indicated that the book includes sections on two particularly heinous Franklin County capital cases. Specifics on spree killer Jerry Hessler, who fatally shot four people in November 1995 and courthouse escapee Alva Campbell, who in April 1997 carjacked and killed 18-year-old Charles Dials while running from authorities, are discussed.

The son of a special agent with the FBI, Smalldon writes his intention for this account was to be “entertaining and instructive” for readers. “That Beast Was Not Me” is set to be released on Aug. 6, 2024, and is available for pre-order at jeffreysmalldon.com.