Rupert Thorne and some of his hired muscle are chilling out in their HQ. Batman busts them, and in doing so, makes his dramatic first appearance in the show.
Rest of the episode:
Batman drives to Batcave, and the viewers (who didn`t already know) find out that he`s Bruce Wayne.
Batman, who has been active for three years, is considered an urban legend. By the large populace. The Gotham PD knows of his existence for certain, though they don`t reveal it to anyone.
In the next scene, Chief Angel Rojas assigns detective Ethan Bennet a partner. Detective ellen Yin. Their job is to capture Batman.
Then we pay our first visit to Arkham Asulym, where a mysterious patient 223 (who broke IN to the asulym) gasses an employee.
Then he releases all the inmates/patients. This makes Batman (who has been at a Gotham Gators-game) to show up. And the cop duo, because they know that Batman will show up.
The pair get to the asulym. Bridge to the island is blown up. They start to swim to it.
Batman finds the gassed employee, who has a hideous, abnormal grin on his face. then he meets the loony who did this to the poor guy. a man who calls himself Joker. They fight and talk. Then Joker scrams.
Batman does the same, and carries the man who has a rictus grin away. Bennett meets Bats, accidentally. But it`s a very brief meeting.
Back to the Batcave, where Bats finds out that the man isn`t dead. Alfred tries to cure him, but it can`t be done without a sample of the gas.
Detective Bennett pays a visit to Bruce Wayne. Does he know that Wayne has a dual identity?
Nah, Ethan and Bruce are buddies. He just wants to talk about the incident he just had.
Later on, Batman tries to find Joker, and get a sample of the gas, so an antidote can be made to counter act Jokers nefarious invention. He does find him. But Joker slips away agin. this time, in a hot air balloon. Filled with the hilarity spreading gas! And he`s going to make it burst!
Batsy goes after him, and a fight in the balloon ensues. Batman saves the citizens, beats Joker up, gets a bit of the gas, ties the villain up and flees the scene. The police protagonists make an another appearance.
The episode ends with the attacked man cured, checking that all the patients are inside their cells/rooms. Joker is. He cites a monologue that makes a slight throwback at one of his origins, and then the credits roll.