Assassination buffs have long held that only deathbed confessions would reveal who really killed John F. Kennedy. That is the premise of "Interview With the Assassin," Neil Burger's pseudo-documentary that begins as a promising meditation on one of America's most durable obsessions but winds up as a slender cinematic stunt.

Dylan Haggerty plays Ron Kobeleski, a San Bernardino, Calif., cameraman whose neighbor Walter Ohlinger (Raymond J. Barry) has suddenly summoned him across the street. Ohlinger is dying -- he only has a few months to live -- and he wants Ron to film his confession that he was the second gunman who shot Kennedy from the grassy knoll above Dealey Plaza.

Disbelieving at first, Ron eventually takes Walter to Dallas, where the lean, laconic ex-Marine walks him through what happened that day.

Trying to corroborate Walter's story, Ron winds up traveling to Washington and finally to Bethesda, where he hopes to capture on camera Walter's co-conspirator as he lies in a Naval Hospital bed.

Meanwhile Ron, who is convinced he's being followed and has rigged his house with surveillance cameras, has become more paranoid than Oliver Stone at a Trilateral Commission meeting.

Burger and cinematographer Richard Rutkowski have filmed "Interview With the Assassin" in the deadpan mockumentary style familiar to fans of "This Is Spinal Tap" and "The Blair Witch Project." In fact, the stylistic conceit is by now so hackneyed that even the most impeccable execution isn't enough to make it compelling.

There is much satirical fun to be had with some of the more colorful supporting players of assassination lore, from the Freemasons to Jack Ruby. But for some reason Burger has opted to make a nondescript road trip, which turns into an equally unrewarding head trip.

Barry delivers a credible portrayal of a man who is either crazy or a homicidal genius, but "Interview With the Assassin" doesn't do justice to the performance. It's just a gimmick, right down to its Washington release date.

Interview With the Assassin (90 minutes, at Visions Cinema-Bistro-Lounge) is not rated but contains some strong language and violence. Writer-director Neil Burger will answer questions about the film tonight after the 7 and 9:30 screenings.

Raymond J. Barry plays an ex-Marine with a dying declaration he wants to make in the pseudo-documentary "Interview With the Assassin."