Bender gets sick in season one's “Fry and the Slurm Factory” and is tested with an F-Ray – which reveals that he has a primitive 6502 microprocessor from an Apple II in his head. “This is straight from me,” Cohen said. “When I was in high school, I spent many of my teen years until five in the morning programming video games of my own invention, so I became extremely and intimately familiar with this chip. It ran at 1 MHz – we’re used to hearing GHz nowadways – and so you had to be a nimble programmer to get it to do what you wanted it to do.” It has since been demonstrated on the show, however, that Bender’s brain is not in his head (it rotates around his body depending on what has broken or exploded), so what gives? “We refer to that as his spine brain, like he has a little brain somewhere at the base of his spine, like a dinosaur. That’s the theory.”
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Leela’s cyclopsed parents can be glimpsed in the upper-left corner of a crowd of mutants in “I Second That Emotion” from season two. “Matt Groening had the idea that Leela would think she was an alien and not born on Earth before we started the series,” Cohen said. “But she wouldn’t find out she was actually a mutant until later.” However, when it came time in season four to really introduce Leela’s mom and pop — Munda and Morris — the writers decided they weren’t quite mutant-y enough, and so they gave them a few added features. “We stared at that freeze frame, and we thought, ‘What can we get away with?’ Ultimately, we knew it would be better if they could have tentacles, so we were willing to put up with a few continuity issues. If we’re called on it, we’ll just say, ‘Your TV was defective!’”
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"Tasty Human Burgers"
In the first season's second episode, Bender stands next to a billboard cryptically written in Alienese – one of three alien languages featured on Futurama. It turned out not to be so cryptic after all: Even at that early date in the series, loyal viewers had already taught themselves to be bilingual and translated the sign to "Tasty Human Burgers." In the premiere, the writers had given an introductory clue to the language by showing a sign that read "Drink Slurm" and later was shown with "Drink" switched to Alienese. “We only gave out five letters, and yet the fans decoded the whole alphabet themselves, within one day, based on context and letter frequency," says Cohen. When the writers developed the language, they also had to decide just what kind of sales pitches an E.T. might make with it. "The language and the human-eating concept went hand-in-hand. As soon as we realized we had to have an alien language, we thought, ‘What don’t they want humans to know?’ So aliens are writing things that if they were to advertise in English, like ‘Tasty Human Burgers,’ we would be alarmed.”
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The Futurama Theorem
The Futurama writers are nothing if not sticklers for scientific and mathematical accuracy. Season six's "The Prisoner of Benda" episode ended with the Harlem Globetrotters proving that it's possible to switch brains with someone else and eventually get yours back. Any other show might be happy with some scrawled gobbledygook (or even just showing the back of the blackboard with a lot of manic scribbling going on on the other side), but these writers are a proud sort, determined to protect themselves against anyone who might check their work. So writer Ken Keeler, who holds a Ph.D. in applied mathematics, actually developed a formula. “I don’t think any other TV show has had the climactic moment be a solved equation!” Cohen said, then goes on to explain Keeler's theory. “The idea is, once you switch brains, you can’t switch back with the person whom you originally switched with, so your only hope is to use multiple people, which raises a complication – is it possible to get your own brain back? We had the story arc before the equation, and then, being the big nerds that we are, we had to figure out if it was possible. And Ken came up with a proof showing that as long as you can find two more people who have not lost their original brain, everybody plus those two can get their brains back. You just always need to keep two designated brains. What could be simpler or clearer?”
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In the show’s very first episode, “Space Pilot 3000,” we see a strange shadow as Fry falls into the cryogenic tube that brings him to the year 3000. Fans of the show will recognize it as Nibbler's – whom we didn't meet until episode four, and didn't learn why he was with Fry on that fateful day until the fourth-season episode "The Why of Fry." “We knew there would be something revealed that would show that Nibbler is a superbeing and not the dumb pet everyone thinks he is,” Cohen said. “But we didn’t know how we would eventually work out the plot. The leading candidate at the time was time travel, but we subsequently decided Nibbler was there already, that he’s lived for over a thousand years, and so we changed the plan. We just knew it would be fun to leave ourselves this epic story to explore later, by planting this shadow.”
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Bring Me the Two Heads of Grover Cleveland
When Fry and Co. enter the Hall of Presidents in the Head Museum in the series premiere, they find all the preserved POTUS noggins — but there are two of Grover Cleveland. “We’re often called on this as having made a mistake,” Cohen said. “So in our own defense, it’s intentional. He had two non-consecutive terms, and we have a couple of real hard-core presidential history buffs in the writers' room, and a lot of presidential figurines in that room." Their fascination with presidents goes far beyond the occasional head joke. "It’s a constant inspiration for us, with the toys lying around. We even have a big competition at lunchtime where the presidents battle each other in hand-to-hand combat, which we base on their estimated physical strength on their day of inauguration – although Nixon went through several rounds not because he was fit, but because we thought he would fight dirty or have a knife hidden in his sock. We spend a lot of time talking about things like this for no good reason.” And writing about them: The commanders-in-chief will reappear in this season's July 28 episode, "All the Presidents' Heads."