Chief of Police, Angel Rojas, assigns Detective Ethan Bennett with a new partner, Ellen Yin, and tasks the pair to capture The Batman, after he publicly acknowledges his existence. Soon afterwards, a break-out of inmates at Arkham Asylum leads Batman to discovering that the culprit is a crazed clown criminal calling himself The Joker, who has a gas that cause victims to be left paralyzed and with a fixed, yellow-toothed smile on their faces. Batman quickly discovers that The Joker plans to use the gas on Gotham City and attempts to stop him, with Yin and Bennett eager to do the same.
