Professor Farnsworth receives word from Mars University that they are revoking his professorship. When he arrives before the university's professors, he reveals all their secrets until he realizes it was his 150th birthday party. After everyone talks about how great he is, Farnsworth becomes concerned with his own mortality. He decides he needs to name a successor. The Planet Express crew expects one of them will be named, including Fry, but Farnsworth reveals that his successor will be a 12-year old clone of himself, Cubert Farnsworth.
Cubert decides that being an inventor is not an appealing career choice, and makes cutting remarks about the Professor and his inventions. A depressed professor makes a recording telling his crew that he has been lying about his age. He is actually 160, the age when robots from the Sunset Squad take people away, never to be seen again. Under cover of an overly-dramatic thunderstorm, a hooded robot arrives, and takes the Professor away while he was saying good-bye to every inanimate object around him.
The crew sets off to rescue the professor, and finds the Near Death Star, the Sunset Squad's base of operations. The crew sneaks in with Fry dressed up as the professor with Cubert on his back posing as a hump to make him look 'old'. They even brought a huge jar of Cubert's blood just in case. They locate the professor, who is unconscious and hooked to a life-support system. They try to carefully disconnect him, only for the robots discover the crew, forcing them to rip him off, and they race back to the Planet Express ship, Professor Farnsworth in tow.
As they reach the landing pad, Cubert is knocked unconscious, but they make it onto the ship in one piece. When the ship takes off, the robots open fire, damaging the engines. Hoping the Professor would help fix them, they try everything to wake him up. A reawakened Cubert announces that he knows how to fix the engines, and the crew makes their escape. (The dark matter engines don't move the ship, but instead move the universe, allowing the ship to go faster than the speed of light.) Safely back on Earth, Cubert tells the Professor that he has decided to follow in his footsteps. The Professor describes his experience on the Near Death Star, as he was hooked up to a virtual reality where he had to do everything an old person would do.