Soper last contacted his family on June 7, 1974. He said he was in Sacramento, California at the time. Following his graduation from college, he had been traveling around the country with truck drivers, offering to help load and unload cargo in exchange for rides. He has never been heard from again. On June 8, 1977, three years later, Soper's clothing and wallet were found in Needles, California. Few details are available in his case, but foul play is suspected. He has brown hair and blue eyes. Soper has a scar on his wrist, a dimple in his left cheek, some freckles, and a cleft in his chin. He had a deviated septum which was surgically repaired. He would be 72-years-old.