The Planet Express crew is hired for their 100th delivery. The recipient of their delivery is Mrs. Astor, a wealthy widow who invites Fry and Farnsworth to her fundraiser. Fry brings Leela as his guest. Mrs. Astor describes how in her youth, she and her husband Mr. Astor rode aboard the Land Titanic, a luxury land roving ship which on its fourth day of its maiden voyage struck a mailbox in Old New York, causing it to sink into the street, killing those who could not escape, including Mr. Astor. To commemorate his memory, she created an endowment in his name, and explains that the fundraiser is to help mutants receive an education in the sewers where they can continue to manage the city's extensive underground sewage system. Leela realizes that the socialites in attendance, including Mrs. Astor, only want to educate mutants in sewage maintenance to keep them busy and distract them from their appalling living conditions and social inequality. Leela confronts the crowd about their prejudice and Fry accidentally reveals Leela as a mutant illegally living on the surface. She is subsequently banished to the sewers to live in squalor with the other mutants. While attempting to appeal to Mayor C. Randall Poopenmeyer on Leela's behalf, the rest of the crew (minus Bender) is also banished to the sewers for two weeks as punishment for illegally harboring a mutant. Meanwhile, to celebrate the 100th delivery, Bender organizes the biggest party of the millennium, but finds the experience empty without the rest of the crew there with him.