All the Rage (1999)

Handguns figure in the intertwining lives of nine people. Warren shoots his wife Helen's lover and his defense is that he thought he was shooting an intruder. She leaves him; the lawyer helps her get a job with a nutty, reclusive computer wizard who waves a pistol about, sometimes at Helen. Tennel, the computer geek's ex-assistant, lands a video-store job and is smitten by Annabel Lee, an aggressive street kid who likes complaining about men to her pistol-packing psychotic brother to set him off. In secret, Annabel starts an affair with the lawyer, who has both a pistol and a gay lover, who becomes jealous. He has a pistol too. A cool (and armed) cop stays on Warren's tail.