Nightwing, Batgirl, Red Hood, and Robin. As his final act, Batman bequeaths a backup base called the Belfry, located in the Union Station Clock Tower, as well as the files of all of his investigations, telling his students that Gotham will need them more than ever once the criminal underworld notices Batman has gone missing. Determined to carry on Batman's will, the four heroes band together to form the Gotham Knights. With the assistance of Alfred Pennyworth, the Knights get the Belfry operational and pursue one of Batman's leads, a scientist named Kirk Langstrom. The Knights find Langstrom murdered, as well as a hard drive containing his secret research. When they infiltrate the GCPD morgue to recover Langstrom's DNA encryption key, they encounter Talia al Ghul, who incinerates Ra's' body and warns the Knights the League of Shadows will make their move on Gotham soon. The Knights then receive a message from Harley Quinn, who has been investigating another lead for Batman while locked up in Blackgate Penitentiary. The Knights recover her intelligence and discover evidence of a centuries-long conspiracy where multiple violent criminals were released early from Blackgate after witnesses to their crimes were mysteriously murdered, with Langstrom being the latest victim. The Knights then confront the Penguin, suspecting he is involved with the conspiracy. The Penguin tells them of the existence of the Court of Owls, a secret society that supposedly rules Gotham from the shadows, and directs the Knights to investigate the ultra-elite Powers Club. The Knights infiltrate the Powers Club, discovering the Court of Owls is real, and manage to escape with an old key. Realizing that Batman had been secretly investigating the Court, the Knights search for all the information they can, but only manage to learn that the Court is allegedly searching for the Fountain of Youth. The Knights use the key to access a secret mine underneath Gotham, where the Court has been synthesizing a compound called Dionesium, a watered-down version of a Lazarus Pit, which they use to create undead super soldiers called Talons. Talia reveals that the League has been observing the Court and are preparing to destroy all of Gotham just to eliminate them, and she advises that the Knights defeat the Court before the League can mobilize. The Knights infiltrate a masquerade party hosted by the Court to discover the identity of their leader and are shocked to find