 On the afternoon of July 1, 1981, Los Angeles police responded to a distress call at 8763 Wonderland Avenue in Laurel Canyon and discovered a grisly quadruple homicide. Drug dealers Ron Launius (Josh Lucas), Billy Deverell (Tim Blake Nelson), Barbara Richardson (Natasha Gregson Wagner), and the homeowner Joy Miller (Janeane Garofalo) were found brutally murdered, bludgeoned to death with lead or steel pipes, and Launius s wife, Susan (Christina Applegate), was left in critical condition. The police investigation that followed -- led by detectives Sam Nico (Ted Levine), Louis Cruz (Frankey G) and Mike Peters -- would unearth a seedy world of drugs and violence, ultimately revealing a motley crew from L. A. s underbelly including ex-con David Lind (Dylan McDermott), nightclub impresario Eddie Nash (Eric Bogosian), and porn legend John Holmes (Val Kilmer) as well as Holmes s estranged wife Sharon (Lisa Kudrow) and his teenage lover Dawn Schiller (Kate Bosworth).