In May 2005, Michael Golub left work to pick up his young son, Mikey, at the home of his ex-girlfriend Shannon and was never seen again. The 27-year-old's disappearance mystified the residents of his hometown, Johnson City, Kan. - a small community of 1,400 people, where everyone knows each other and each other's business. Golub's family says he would never have given up his son for any price, and there is no doubt in their mind that he was murdered. Yet one piece of important evidence has always been missing: Michael Golub's body has never been found. Now, "48 Hours Mystery" has brought in two private investigators to examine the evidence and uncover what they think happened to Michael on that summer evening. They reveal new facts about the case and new theories as to what happened to Michael Golub, and why. Did Golub suddenly leave town to make a new life for himself? Or was he brutally murdered? And if so, would his family ever get justice? It would take two trials to get even close to an answer. Correspondent Susan Spencer reports.