Futurama Episodes

After Bender dumps toxic waste into the sewers, the mutants become angry and kidnap Bender, Fry and Leela. They suspend the crew over a radioactive lake and threaten to dump them in, altering their human genes and mutating them, but two hooded mutants save them. Leela decides to pursue the mysterious mutants, who seem to have a suspicious fixation with her.
wikipedia.org summary:
Dr. Zoidberg’s mysterious miracle cream gives Fry and Leela superpowers. Teaming up with Bender, they form the New Justice Team, under the respective alter egos of Captain Yesterday, Clobberella, and Super King. But Leela’s new duties as a superheroine put a strain on her relationship with her parents.
imdb.com summary:
Bender sets up a successful waste disposal business. But because he dumps everything in the sewers, the Sewer Mutants revolt and sentence Bender, Leela and Fry to be dumped in the Mutagenic Sewage lake. Somehow two robed mutants with an interest in Leela manage to persuade the Supreme Mutant to let them go.