Batman Beyond, WB (reruns on Hub)
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Part of the DCAU (see Batman: The Animated Series). The show is set roughly 50 years in the future, and Bruce Wayne is retired from both Wayne Enterprises and his secret life as the Batman. The old supervillains are pretty much gone, but Gotham is still full of crime. There are of course the Jokerz, a gang of kids who model themselves after the Joker, at least in costume. They're basically pretty lame, though. A much bigger problem is Derek Powers, who now runs Wayne-Powers (a company created when his merged with Bruce Wayne's).
One of Powers' employees finds out about one of his deals to sell a newly developed toxin to foreign countries to kill their enemies rather quickly and grossly. Powers has this employee killed. The man's son, Terry McGinnis, will find evidence of this and bring it to Bruce Wayne. Terry will discover Bruce's secret, that he used to be Batman, and Terry will become the new Batman. Meanwhile, Terry exposes Powers to his own toxin, and Powers then has his people try to cure him with intense radiation therapy, unexpectedly mutating him into Blight, a new radioactive villain. This will remain a secret for only so long, before Powers' equally treacherous son, Paxton, takes over Wayne-Powers.
Meanwhile, with a new Batman in town, of course new supervillains will start crawling out of the woodwork. We'll occasionally see some familiar ones as well as ones Bruce used to fight that we've never seen before.... What else? Terry has a friend named Maxine. And a girlfriend named Dana. And he has to go to high school of course. And stuff. And there's new slang words, like "shuay" and "twip." New technology; Batman wears a very advanced suit that makes him stronger, lets him fly, has a radio/video link to the Batcave for Terry to communicate with Bruce, and turn invisible, and stuff. Also the new Batmobile is more like the Batwing than a car; but then, all cars seem to have hover capabilities. There are other new forms of technology, too, as well as old ones. There's some cute girls, too. We like Ten. And Inque. And Inque's daughter. And Derek Powers' secretary. Anyway, it's a pretty cool show. Not as good as the real Batman, of course, but still....
There's also a movie called Return of the Joker (IMDb), which is way shuay. There's also a spin-off series called The Zeta Project, about a robot named Zeta who Terry met in one episode of Batman Beyond.