Among unsolved murders of celebrities, the slaying of TV actor Bob Crane has remained one of the oddest and most disturbing. Millions of Americans knew Crane as the star of Hogan's Heroes, the popular sitcom about American POWs in Nazi Germany that ran from 1965 to 1969. In June of 1978, Crane's skull was smashed in at his Scottsdale, Arizona, apartment. The murder led to the discovery of his secret life: he starred in homemade pornography. Although police suspected Crane's friend and sex film partner, John Henry Carpenter, they did not have sufficient evidence to charge him. Surprisingly, fourteen years later, the case was reopened. But a jury acquitted Carpenter in 1994, leaving the identity of the actor's murderer a mystery.

Born on July 13, 1928, Bob Crane quit high school at the age of sixteen to become a percussionist. Starting in 1950, he enjoyed a meteoric rise in the radio business, within five years...