Jim Sullivan was the kind of California character who seemed to have stepped straight out of a Pynchon or DeLillo novel — a 6-foot-2 singer and songwriter known as Sully with a magnetic personality and a handlebar mustache. His dramatic psych-folk songs were spacious, cinematic and edged with mystic, lonesome brooding. His social circle included actors and Hollywood hangers-on, and he’d had brushes with fame, including an uncredited part in “Easy Rider” with his friend Dennis Hopper.

On his 1969 debut album, “U.F.O.,” he sang of beckoning highways, of aliens, of an Arizona ghost town, of a man who looked “so natural” in death it was clearly his time to go. Six years later, the 35-year-old Sullivan disappeared in Santa Rosa, N.M. On the front seat of his recovered gray VW bug were his ID, his beloved 12-string Guild guitar, and a box of his two albums, “U.F.O.” and the 1972 LP “Jim Sullivan.”

Sullivan, a country-blues troubadour with an enigmatic story, has been compared to Nick Drake, Richie Havens and Gram Parsons. Questions about his vanishing still plague the small town where he was seen last, as well as his family and a small group of loyal enthusiasts. Last month , the record label Light in the Attic reissued his self-titled album, along with a new collection of previously unreleased demos, titled “If Evening Were Dawn,” that deepen Sullivan’s eerie, essential strangeness.