Back when JFK reopened the floodgates for new theories about the Kennedy assassination, director Oliver Stone referred to his reckless amalgamation of facts and speculation as a "counter-myth," implying that no conclusions were definitive, especially the one issued by the Warren Commission. The film had no convincing revelations of its own, but it did succeed in muddying the official record enough so that the single-shooter theory no longer seemed plausible. Catnip for conspiracy buffs, writer-director Neil Burger's clever mockumentary Interview With The Assassin forwards a counter-myth that's considerably more plausible that Stone's, even though it's a complete fabrication. Smartly conceived and meticulously executed, if too slight and gimmicky to have much resonance, the film jumps off from the idea of a second shooter in the grassy knoll and wonders what would happen if he came forward to tell his story. Though he doesn't use the same "found footage" conceit, Burger's faux realism and first-person camera technique owe a debt to The Blair Witch Project, but at least he approaches the same startling level of verisimilitude. In a quiet, middle-class California subdivision, unemployed TV cameraman Dylan Haggerty gets coaxed into filming the confession of neighbor Raymond J. Barry, a shady ex-Marine who claims to have been the second gunman in Dallas on Nov. 22, 1963. With terminal cancer leaving him with five or six months to live, Barry has decided to break his 37-year silence and stake out his place in history, even though his decision puts both men in immediate danger from larger conspiratorial forces. In proving his case, Barry takes Haggerty on a wild goose chase around the country, from a safe-deposit box where he keeps the empty shell casing to the scene at Dealey Plaza to the Norfolk home of his former commanding officer, who allegedly recruited him for the job. With a sly, teasing drawl and a chilling air of detachment, Barry's performance sustains Interview With The Assassin long after its premise has worn thin, filling out Burger's psychological profile with convincing mirthlessness and paranoia. His braggadocio seems appropriate both for the man who shot JFK and for a man who would pretend to have done so; in one scene, he even mugs for pictures with a couple of tourists in the Plaza. But for all its apparent skill, the film never squeezes out of its own gimmick enough to comment with any seriousness on this epochal event and its ramifications. Seeing Interview With The Assassin is like meeting a colorful conspiracy nut at a party and indulging him politely before quietly slipping out the door.