This gutter-punk cult movie about an unlikely bar band’s rise and fall might’ve been scripted during a drunken Russian-roulette session among Charles Bukowski, Lars von Trier, Harmony Korine, and Irvine Welsh. Flemish source novelist Herman Brusselmans clearly relishes the same lowlife milieu as Welsh’s Trainspotting, and director Koen Mortier has surely studied that movie. Here, a manipulative, cynical novelist (our narrator) agrees to play drums with three variously handicapped losers—half-deaf, quarter-paralyzed, and full-blown sociopath. To join them for a battle of the bands in what looks to be Belgium’s only Hell’s Angels clubhouse, the writer must first admit to a handicap of his own. Could it be…a lack of conscience? He needs material, and his Belgian white-trash bandmates have ample squalor and grotesquerie to supply. Which includes sexual assaults, child neglect, copious vomit, and a tuneless but effective cover of Devo’s “Mongoloid.” Ex-Drummer‘s tone is lurid, rude, exaggerated, sometimes comic, and occasionally hypnotic. (The band is introduced in nearly 10 minutes of reverse-motion footage; the singer lives upside-down on the ceiling of his crumbling apartment.) The shock value is fun for a while. But Ex-Drummer, like the phallus of a character called “Big Dick,” goes on too long. Sour, selfish literary ambition deserves its comeuppance, yes. But where is the appreciation for music, however ineptly performed?