The Most Dangerous Animal of All

A New York Times Bestseller
A San Francisco Chronicle Bestseller

Soon after his birthmother contacted him for the first time at the age of thirty-nine, adoptee Gary L. Stewart decided to search for his biological father. His quest would lead him to a horrifying truth and force him to reconsider everything he thought he knew about himself and his world.

Written with award-winning author and journalist Susan Mustafa, The Most Dangerous Animal of All tells the story of Stewart's decade-long hunt. While combing through government records and news reports and tracking down relatives and friends, Stewart turns up a host of clues—including forensic evidence—that conclusively identify his father as the Zodiac Killer, one of the most notorious and elusive serial murderers in history.

For decades, the Zodiac Killer has captivated America's imagination. His ability to evade capture while taunting authorities made him infamous. The vicious specificity of his crimes terrified Californians before the Manson murders and after, and shocked a culture enamored with the ideals of the dawning Age of Aquarius. To this day, his ciphers have baffled detectives and amateur sleuths, and his identity remains one of the twentieth century's great unsolved mysteries.