Robert "Bob" Christian (4 of Spades, Wisconsin)

In the Fall of 1977, Bob was just weeks into his freshman year at UW-Madison. He was a math whiz with a knack for computers and a big heart. At 18-years-old, there was no telling how far he’d go. But no one ever expected to be asking the question… Where did he go? Yet here we are almost half a century later, with that burning question and just a string of bizarre clues that leads many to believe an infamous serial killer could be to blame for his disappearance.