Robert Matthew Bockmann, known as Robbie, was 26 when he disappeared from Boulder, Colorado, on April 18, 2003. He had moved to Colorado from Texas three weeks earlier to live with his mother and brother. A self-taught guitarist and songwriter, he was also a father who was reportedly deeply distressed following a recent divorce and separation from his young daughter and had a history of severe depression and prior suicide attempts.

On the day he was last seen he mentioned plans to ride a bicycle up Flagstaff Mountain and had purchased flowers for a friend. His silver Dodge Neon with Texas plates was found the following day abandoned at the South Boulder Creek Trailhead at Walker Ranch. Personal items, including his wallet with ID and $50, were inside the car; there were no immediate signs of foul play. He is described as a white male, blond hair, blue eyes, 5 feet 10 inches, 170 pounds, muscular, with a long scar on his inner left forearm from wrist to elbow.

Extensive searches of the steep, rugged Walker Ranch terrain turned up no trace of him. The area is home to wildlife such as bears and mountain lions, and his family has said they believe he may have taken his own life in a way that would make recovery difficult. Anyone who knew Robbie or has information about his movements around April 18, 2003, is asked to come forward.