After an episode that was a little too topical for my tastes, "The Prisoner of Benda" was just the right style of "Futurama" episode for me. It mixed zany situations with unbelievable science fiction to put together 20 minutes of pure insanity.
The crux of the episode centered around the professor's mind-switching machine, which worked, but was quickly discovered to have a flaw: once two people swapped minds, they couldn't swap directly again. Now this set up some ridiculousness with people in other people's bodies, switching every which way but right (at least until the end when the Harlem Globetrotters showed up with the proper math and body solution to the problem).
Amy ended up in Leela's body and just kept eating and eating until she was a fat tub. Farnsworth ended up in Bender and joined a robot circus as "Nonchalanto". Bender ended up in a Robo-Hungarian Emperor, who was the subject of a traditional identity switch trope -- making the poor peasant thinking they're getting the good side of the deal when really they've ended up the target of an assassination plot.
But the best switches involved Leela and Fry. Leela ended up in Professor Farnsworth's body, and was upset because she thought Fry only liked her for her body (when in reality, Fry dating his distant nephew would just have been gross). So, to prove that Leela could be just as shallow as Fry, he switched bodies with Zoidberg. This led to the two of them going on a date, where they tried to out-gross each other out, and ended up... making out on top of a restaurant table... which led to them having sex. That's right. Fry and Leela had sex as Zoidberg and Farnsworth. This was so disgusting it was amazing (note: we didn't actually see the sex on screen, just the post-coital snuggling, but still, so gross it was awesome).
The other great scene in this episode involved Scruffy and his robot wash-bucket, who was in Amy's body at the time. I can't do it justice, so I'll just show you.
The antics between the Emperor (in wash-bucket, pretending to be Bender) and Zoidberg (in Fry) were also top notch. All-in-all, this episode didn't really make much sense, but Futurama has proven through the years that it can do a nonsense episode and have it be sublime.
Now, on to this week's best lines:
Linda: Tonight at 11…
[Nothing like a short and sweet cold open to set the tone for a very funny episode]
Farnsworth: As a man enters his 18th decade, he thinks back on the mistakes he's made in life.
Amy: Like the heaps of dead monkeys?
Farnsworth: Science cannot move forward without heaps!
Amy (in Farnsworth's body): Oh no! Is it possible to get everyone back to normal using four or more bodies?
Farnsworth (in Bender's body): I'm not sure. I'm afraid we need to use [dramatic music and close-up] MATH!
Fry: So now Leela's all crotchety because she thinks I'm not attracted to her in the professor's body.
Hermes: You aren't, are you?
Fry: Of course not! But I was willing to lie about it. What more can a man do?
Zoidberg [In Fry's Body]: Ah-ha! The guy in this body has a friend! [To wash-bucket-bot] Bender old pal! It's me! The Fry!