Ep 18. World's Finest: Part 3

Batman arrives in Metropolis and teams up with Superman to take down their mutual enemy, the Joker, who is in town to plan a major heist. As the two heroes work together, they also clash over their differing methods and approaches to crime-fighting. Meanwhile, the Joker teams up with Lex Luthor and his personal assassin, Mercy Graves, to carry out their plan, which involves a deadly gas and a powerful weapon. Can Superman and Batman put aside their differences to stop this dangerous trio and save the city? Find out in the thrilling conclusion of the three-part "World's Finest" saga.