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Criminal Investigative Failures

The Unknown Darkness


The Unknown Darkness

Mr. McCrary has co-authored the book “The Unknown Darkness: Profiling the Predators Among Us” with Katherine Ramsland, Ph.D.

The work of Mr. McCrary—including some of the cases in the book—were featured in the hour-long season premier of “48-Hours Investigates” on CBS. The show aired on September 20, 2003.

Note: Mr. McCrary would gladly autograph your purchased copy of his book. Simply send it to:

Behavioral Criminology International
11402 Seymour Lane
Spotsylvania, VA 22551

Be sure to include return postage.

Critical Praise

“In a book that combines engrossing writing with seasoned insight, McCrary, a 25-year veteran of the FBI and a former criminal profiler in the bureau’s renowned behavioral science unit, has teamed with Ramsland, a forensic psychologist and writer, to produce a detailed account of criminal investigative analysis. He describes 10 cases that provoked frenzied storms of media attention in their time including the FBI standoff with the David Koresh and the Branch Davidians, the murder of two Canadian teenagers by a husband and wife team, the hunt for an international serial killer and the infamous Sam Sheppard murder case which came to court for a third time nearly 50 years after it occurred.

...The book offers plenty of shockingly grisly and strange details to fascinate and horrify. But McCrary’s levelheaded professionalism and consummate expertise elevates his work above the throng...”

Publishers Weekly
May 26, 2003

“Gregg McCrary has distinguished himself as one of the world’s foremost criminal profilers and crime analysts. With special training in mental discipline, he looks beyond the obvious and catches what other profilers miss. Read this book and you will understand how his insight has helped solve many difficult crimes.”

Dr. Henry Lee
Director of the Connecticut State Police Forensic Science Laboratory and author of Cracking Cases

The Unknown Darkness is one of the most immensely readable and gripping accounts of serial murder I have ever read. Gregg McCrary is one of the great detectives of his time. He helped create the science of criminal profiling. Those amazing early days at Quantico, fictionalized in the The Silence of the Lambs, have now become almost as legendary as the Wild West.”

Colin Wilson
Author of more than sixty books, including Serial Killers: A Study in the Psychology of Violence

“This is a must read for true crime fans! The Unknown Darkness is an intense close-up look at the hunter and the hunted in incredible games of cat-and-mouse! Behavioral Science veteran McCrary is both modest and brilliant as he tracks down the predators among us. Beautifully written, expert analysis on high-profile killers! True crime readers and students of the criminal mind will leap upon this book and they won’t be disappointed! A masterpiece!”

Ann Rule
Author of The Stranger Beside Me, Every Breath You Take and A Heart Full of Lies