Ra's al Ghul hired the Joker to distract Batman and Robin. During the fight, Joker kidnapped and beat Jason with a crowbar. Before Batman could get to Jason who was trapped inside the warehouse, the bomb the Joker had set up exploded. With the unnecessary death of Jason weighing on Ra's mind, his guilt drove him to secretly take the body to the Lazarus Pit in order to bring Jason back to life. The Pit had affected Jason's mind. Using the past alias of the Joker, Jason took up a more aggressive type of crime fighting as the Red Hood.
Eventually, Jason confronted Batman and the two engaged in a fight. After Batman refused to kill the Joker, Jason shot at him but he swiftly dodged the bullet. The Joker then exploded the building, leaving Jason's fate unknown though he is presumably finally at peace. However, a few days later, Alfred approached Bruce on whether to take down Jason's memorial. Bruce refuses, saying 'this doesn't change anything'.