Tobias Whale is the most powerful gangster in Gotham City, and, after years of trying, Lt. Gordon finally has the evidence to put him away for good. But Whale is not going to be "harpooned" easily. After his lawyer demands that Gordon release Whale, Gordon's daughter Barbara is kidnapped. With no other options and time running out, Gordon is forced to ask Batman for help. While monitoring Whale's men, Batman learns that Barbara has been taken to "The Cauldron" (a former industrial park that became the most dangerous part of the city following the financial crisis years ago) which is populated by a gang of criminals known as "the Ghosts." With Katana's help, Batman stages a raid on the Cauldron. But the real threat here is not the Ghosts, but the man guarding Barbara: Whale's chief enforcer, Phosphorus Rex!