Bruce Wayne (David Mazouz) becomes more determined than ever to capture the person responsible for his parents' death. This prompts him to seek the help of Detective James Gordon (Ben McKenzie) in episode 19 of "Gotham" season 2.

The trailer for the episode, titled "Wrath of the Villains: Azrael," shows a flashback to the events that happened in season 1, when Bruce's quest for vengeance led him to his friend Selina Kyle (Camren Bicondova), who lent him a gun that he could use to kill the hired murdered Patrick Malone (Michael Bowen). But the young billionaire changed his mind when he was about to point the gun at Patrick, who later on committed suicide when he was about to be arrested by Gordon.

Despite Patrick's death, Bruce and Gordon continued their investigation into the Waynes' murder, and they later on found out that it was Thomas Wayne's (Grayson McCouch) former friend, Professor Hugo Strange (BD Wong), who hired Patrick to end their lives.

The upcoming episode will center on Gordon's investigation into Professor Strange's mysterious Project Chimera that operates inside the secret underground Indian Hill facility. Based on the trailer, he will find out that Strange is doing an experiment that brings dead people back to life.

Gordon will inform Gotham City Police Department Captain Nathaniel Barnes (Michael Chiklis) about his findings, which the latter will simply dismiss.

"So in a nutshell, Hugo Strange is making monsters out of dead people in his spare time?" Barnes tells Gordon in the promo trailer. Gordon replies that he knows that the idea sounds far-fetched, but Barnes disagreed. "It sounds insane," the police captain corrects him.

The trailer also shows the reappearance of Theo Galavan (James Frain), whom Gordon shot dead in the first half of the season. But this time, Theo is no longer the handsome billionaire that he was known for. Instead, he calls himself Azrael and vows to make Gordon's life a living hell.

"Gotham" season 2 episode 19 airs on Fox on Monday, May 2.