In 1985, then-18-year-old Tom V. Odle--fueled by LSD intoxication--stabbed his parents to death then killed his sister and two brothers. The shocking crimes happened just a couple of hours away in Mt. Vernon, Illinois.

Now, the 47-year-old Odle has collaborated with neuropsychologist Robert Hanlon on a book called  "Survived By One: The Life and Mind of a Family Mass Murderer." 

The book's aim is to dissect the crime and determine why someone would commit such a heinous act. According to Hanlon, Odle's motive for the brutal killings was revenge and that his mother was the main target.

Odle's mother, according to the book, was very abusive toward him and his younger brother Sean. Hanlon supposes that the murders committed beyond Odle's mother can be traced back to the added aggression of his drug use.

Hanlon's research has led to the discovery that most impulsive crimes like this--by so-called "family annihilators"--are often the work of someone who is mentally disturbed, but, as Hanlon notes, Odle doesn't fit THAT profile.

Dr. Hanlon hopes that his book will raise awareness of the possibility of crimes like Odle's. As Hanlon says, "We have to care more about this and pay attention to it."