F. Scott Fitzgerald was wrong: there are second acts in American lives. But all too many of them are sad, sordid or both, as this fact-based story of sex, drugs and murder featuring adult-movie superstar John Holmes aptly demonstrates. In July 1981, Los Angeles newspapers were plastered with the grisly details of what police dubbed the "four on the floor" killings. Four people were hammered to death with lead pipes at 8763 Wonderland Avenue, and a fifth was beaten insensible. What gave the case an extra shot of tabloid oomph was the rumor that fading but still legendary porn-star Holmes (whose turbulent life and times inspired the character of Dirk Diggler in P.T. Anderson's 1997 BOOGIE NIGHTS), was involved. Co-writer/director James Cox's jittery, RASHOMON-style examination of the Wonderland killings is driven by Kilmer's mercurial performance as the fading sex-film phenomenon, whom friends and acquaintances variously described as a none-too-bright sweetheart, a selfish bastard and a treacherous base-head who'd pimp his mother for a fix. The establishing version of the tale, related by biker David Lind (Dylan McDermott), lays out the elements. A pair of stolen antique guns that Holmes, who'd been cadging drugs from lowlife Ron Launius (Josh Lucas), was supposed to sell to a wealthy friend; Launius's house on Wonderland Avenue, a non-stop hive of drugging, dealing and stealing; Holmes's oily pal, Eddie Nash (Eric Bogosian); and Launius's crew — wife Susan (Christina Applegate), partner Billy DeVerell and his girlfriend (Tim Blake Nelson, Janeane Garofalo), and Lind's girlfriend (Natasha Gregson Wagner). The Wonderland crew robbed Nash and, Lind believes, were in turn targeted by the vengeful Nash; though absent the night of the killings, Lind fingers Holmes as the traitor who led Nash's thugs to their victims. Holmes, by contrast, casts himself as the victimized party, a junkie with a $1,500 a day coke habit exploited by his Wonderland cronies on the one hand and the sadistic Nash on the other; he insists he didn't even witness the killings. Yet a third version of events suggests that the hands of everyone involved were dirtier than they're willing to admit. Cox and co-writer Captain Mauzner don't pretend to reconstruct a definitive account of events. Their interest lies in the provocative fragments of story that add up to an elusive but dazzlingly sleazy examination of addiction, selfishness, greed and self-destruction in the California sun.