Batman and Constantine have teamed up to investigate the murder of the Joker. Their investigation leads them to an underground nightclub in Gotham. Constantine reveals to Batman that he has a source in the club that might have information on what really happened to the Joker. Batman enters the club only to discover that the source is Etrigan The Demon Knight. Etrigan performs at the club as a rapper and has a huge influence on the crowd. Meanwhile, Gotham is attacked by the "Joker" and Batman races to the top of the GCPD building for answers. [...]