It was one of the most beloved and strangest sitcoms ever -- Hogan's Heroes.
It took place in of all places, a German prison camp during World War II, not exactly fertile grounds for comedy.
The star of the show was Bob Crane. For six seasons, Crane played the wise-cracking American P.O.W, Colonel Hogan.
Now, Bob Crane's eldest son, 64-year-old Robert Crane, new book, Crane is about his father's "unsolved murder." It investigates the 1978 homicide, one of the most enduring mysteries in Hollywood history.
Robert Crane told INSIDE EDITION, “He made some bad decisions, the people he hung out with.”
Bob Crane was married to his Hogan's Heroes co-star, the beautiful Sigrid Valdis. But in his private life, he was a notorious womanizer, as depicted in a 2002 movie about his life starring Greg Kinnear.
He and a friend, John Carpenter, actually videotaped themselves in comprising positions with many of their conquests.
Robert Crane says when he was a teenager, his father admitted he had a secret life.
He said, “I was hearing more and more of it, then with the video tape thing and my dad basically being an open book, you know he would show me photographs of women on the road. I’m 15 years old, I’m seeing things my friends are not seeing from their dads."
In June 1978, Bob was appearing in a dinner theater production in Scottsdale, Arizona. Hours after a video of the rehearsal was taken, his co-star, Victoria Berry, found the star bludgeoned to death inside an apartment.
For years, the crime remained unsolved. Then 12 years later, it was reopened and Carpenter was arrested. A jury, however, found him not guilty. He died in 1998.
Officially, the case remains unsolved. But Bob Crane's son says he believes Carpenter may have done it. He also says there is another suspect and it may shock you who it is.
Robert believes it's his own stepmother, Sigrid Valdis.
Robert said, “He wanted to get away from his second wife who turned out to be a nightmare. She's the only person who gained anything financially. It wasn't a fortune. It was comfortable for it's day in 1978. She got it all.”
Valdis died at age 72 in 2007. She lies buried next to Bob Crane.
Robert Crane says his father was possessed by demons that very likely led to his violent death.
“He was like a mad scientist who dealt in photographs of women, videotapes. He loved women and he loved cameras you put them together there you go,” he said.
Watch Below: Parents of Teen Murdered by Facebook Killer Share Advice to Keep Your Kids Safe