"The Prisoner of Benda" is the tenth episode in the sixth season of the American animated television series Futurama, and the 98th episode of the series overall. It aired on Comedy Central on August 19, 2010. In the episode, Professor Farnsworth and Amy build a machine that allows them to switch minds so that they may each pursue their lifelong dreams. However, they learn that the machine cannot be used twice on the same pairing of bodies. To try to return to their rightful bodies, they involve the rest of the crew in the mind switches, leaving each member free to pursue their own personal endeavors in a different crew member's body. The episode is composed of multiple subplots, with the main subplot being Bender attempting to steal a crown, but ending up switching places with the Robo-Hungarian emperor.
The episode was written by Ken Keeler and directed by Stephen Sandoval and was met with acclaim from critics. The issue of how each crew member can be restored to their correct body given the limitation of the switching device is solved in the episode by what David X. Cohen described in an interview as a mathematical theorem proved by Keeler, who has a Ph.D in Mathematics. The title and the story's main subplot is a reference to the 1894 adventure novel The Prisoner of Zenda by English novelist Anthony Hope. Series writer Eric Rogers considers this his favorite episode of the season.
Plot
The episode begins with Emperor Nikolai of Robo-Hungary visiting. Bender voices a desire to steal his crown, but no one is willing to be his accomplice.
Meanwhile, Professor Farnsworth switches consciousness with Amy using a new invention so that he can relive his youth. Likewise, Amy longs for her younger days of constantly eating and wishes to use the Professor's skinny body to gorge herself with food for a while. However Amy finds that the Professor's aging body simply cannot digest like it used to, while Farnsworth finds that Amy's human body cannot take the thrills he is seeking out. Even as they give up, they find they cannot revert to their own bodies, because the device will not operate on the same pairing of bodies. The Professor first suggests they might be able to switch back to their original bodies with a third person. Bender volunteers and switches bodies with the Professor (in Amy's body) so he can perform a robbery without being identified. As Bender rushes out, the Professor realises that the three of them still will not be back in their real bodies, so he decides to run away in Bender's body and join the Robot Circus, renaming himself Nonchalanto and performing foolhardy stunts for cheap thrills.
Bender — now in Amy's body — goes aboard Nikolai's yacht, planning to steal his crown. He knocks out Nikolai's first officer and cousin. After binding and gagging him, he realizes his timing is off and accidentally throws his watch through a metal detector. He is then captured by the Emperor. When Bender states that he is really a robot who has switched bodies with a human, Nikolai reveals that he feels trapped by his wealth and wishes to live the life of a normal, "peasant" robot for a while. With Bender unable to find his real body, he tricks him into switching bodies with the robot Washbucket and inhabits Nikolai's body, planning to live the life of an Emperor. Washbucket, now in Amy's body, professes her love to Scruffy, and even suggests they run away together, but he sadly turns her away, reminding her that he is still a man and she is janitorial equipment.
At the circus, the Professor is having a fine time as the world's most indifferent robot daredevil, when he meets the Grande Dame, the robot cannon Big Bertha. He politely asks if he could be shot from her, but she admits that she is so old, it would end her life. He asks if she would like a new, young body, but she turns him down briskly, telling him that her body may be old, but it is still hers to treasure, giving him pause for thought.
