Paradise Lost 3: Purgatory is a 2011 American documentary film directed by Joe Berlinger and Bruce Sinofsky, and sequel to their films Paradise Lost: The Child Murders at Robin Hood Hills (1996) and Paradise Lost 2: Revelations (2000). The three films are about West Memphis Three, three teenage boys accused of the May 1993 murders and sexual mutilation of three prepubescent boys as a part of an alleged satanic ritual in West Memphis, Arkansas. Purgatory offers an update on the case of the West Memphis Three, who were all recognized guilty of the murders in 1994 but kept on claiming their innocence since then, before culminating with the trio's attempt at an Alford plea.

The film premiered at the 2011 Toronto International Film Festival on September 11, 2011, before airing on HBO on January 12, 2012. It received a nomination for the Academy Award for Best Documentary Feature, as well as Primetime Emmy Award nominations for Exceptional Merit in Documentary Filmmaking and Outstanding Directing for Nonfiction Programming.