Tippy Tinkletrousers (A.K.A Professor Poopypants) was a genius and inventive scientist from New Swissland. He is a recurring character in the novels and the main antagonist of the film.
In the books, he is insane, absent-minded, crazy, cool, calm, zen, forgetful, streetwise, kooky, and smart all at the same time. In the movie, he is dangerous, murderous, rude, grumpy, psychopathic, grouchy, selfish, crazy, insane, mischevious, and ruthless.
Professor Poopypants was born in 1936 in New Swissland he created the Goosy-Grow 4000 and the Shrinky-Pig 2000 as he wanted to solve global problems. He moved to America because he wanted to share his inventions with the world and solve the biggest problems they had, but had trouble as he was laughed out of every single important college he had enrolled in.
He got a job at Jerome Horwitz Elementary School in Piqua, Ohio as a science teacher, replacing Mr. Fyde who resigned. Everybody laughed at his name. He soon invented the Gerbil Jogger 2000 and showed it to the class. Everyone was impressed by it until they found out that his middle name was Pee-Pee, thanks to a snide remark from George and Harold. Later, he read a comic that the boys had wrote called "Captain Underpants and the Pied Pooper of Piqua". It destroyed his last bit of sanity and made him go crazy with revenge.
Using the Goosy-Grow 4000, he makes the Gerbil Jogger 2000 grow as large as a building and then gets inside. He shrinks the school and holds everyone in it hostage. He then unveils his plan to force everyone on Earth to change their names so that everyone will have a silly name instead of a normal one, and anyone who refuses will be shrunk. Professor Poopypants does this first on Mr. Krupp, who becomes Lumpy Pottybiscuits. All the children find this funny, until Professor Poopypants forces them and the staff members to use the chart to change their names as well.
George and Harold (now Fluffy and Cheeseball) find Mr. Pottybiscuits and turn him into Captain Underpants (now Buttercup Chickenfanny, but he refuses to change his name) to steal Professor Poopypants' enlarging machine, but unfortunately he gets caught and the Professor shrinks both him and the machine down in the process.
Fluffy and Cheeseball get on the roof of the school to try to enlarge it (along with the students and teachers) back to normal size, but get noticed and thrown off the school by Professor Poopypants, but Cheeseball makes a paper airplane that Fluffy enlarges. The plane flies into many threats, yet Captain Underpants rescues them and they end up in an abandoned alley. Fluffy tries to enlarge Captain Underpants (accidentally enlarging Cheeseball's right hand) to the size of Professor Poopypants' gerbil machine. Captain Underpants was now visible so he gets enlarged again so he could fight Professor Poopypants. Professor Poopypants was ultimately defeated and everyone gets their names back. The boys use the shrinking and enlarging machines to grow the school and shrink Captain Underpants back to normal size. Then Captain Underpants gets soaked with water, turning him back to Mr. Krupp.
Professor Poopypants is then hauled off to jail. On the advice of George and Harold, he changes his name so no one will make fun of it anymore (which he hadn't thought of until George noted that to him). Sadly, he chooses his maternal grandfather's name, Tippy Tinkletrousers, which the people at jail make fun of.
Tippy appears in the Book in George and Harold's prologue, summing up his involvement in the last book.
When George and Harold arrive in the alternate universe, Pippy Pee-Pee Poopypants/Tippy Tinkletrousers was seen as a good guy. He was working for the fire department along with Zorx, Klax, and Jennifer, who also became good.
At the end of the book, Tippy actually appears in a giant pair of robotic trousers and gets angry at two cops that laugh at his name. He then freezes the cops with his latest invention: The Freezy Beam 4000. He then announces "It's time for my revenge!". He then chases after George, Harold, Sulu and Crackers.
It is revealed here that what happened at the end of the eighth book did not originally happen, as Tippy and the robotic trousers were actually from the future and interrupted what was supposed to happen. In the original timeline, after George, Harold, and Mr. Krupp are arrested, Tippy reveals his newest robotic suit to his prisoners by claiming that he is building a statue for the warden. He then takes Mr. Krupp and breaks both of them out as he wishes to find George and Harold and get revenge on Captain Underpants for throwing him in prison.
He succeeds in finding the two boys due to Mr. Krupp telling him they are in the Piqua Juvenile Detention Center, but George and Harold snap their fingers in front of him, transforming him into Captain Underpants, but revealing to Tippy who the Captain is when not fighting crime. The Captain goes off to find a cape which he finds in the Everything Except Fabric Softener Store.
Tippy then interrogates the boys on everything they know about their superhero until the Captain arrives. They fight, but the Captain defeats the Professor with ease before the Captain tricks the Professor into freezing the suit's feet. The Captain then rips off the top of the suit, reducing it to the robotic trousers as seen at the end of Book 8.
Realizing that the Captain is too powerful for him to beat, the Professor decides to go back in time five years ago to escape from him. Tippy does so and successfully escapes from Captain Underpants. When Kipper Krupp and his friends run from an apparent ghost, Tippy appears in front of the sixth graders in his robot pants and states that it looks like they have seen a ghost. This causes the four boys to go insane and be taken to a reality-challenged institute as well as leaving Mr. Krupp to be blamed for all the events that happened in his school. He is fired from his position as principal due to everyone blaming him. Tippy, not realizing what he had just done, goes back to the future while also noting that kids 5 years ago were really different than he thought they were.
However when he returns, he sees the future ruined and destroyed. He learns from a small boy that the moon got blown up by Dr. Diaper, talking toilets started rampaging around the city, and giant zombie nerds began terrorizing the town. Realizing that he had created a huge mistake, the Professor tries to get back into his robot pants and undo the entire mess, but he is seemingly squashed by the giant zombie nerd George and Harold before he could do so.
However, it's revealed that Tippy was not killed by the Zombie Nerd Harold, because zombie nerds are slow due to their incredible size and Tippy faked his death by placing a bag of ketchup under Harold's feet. Tippy went back in time to before he drove the bullies insane and froze them before they could see him. He shrunk his younger self and returned to the present with him. When the bullies thawed, history was restored to normal.
Tippy confronted George and Harold and froze the cops as was depicted at the end of Book 8. He attempted his revenge on George and Harold, but they escaped him and went back in time to return Crackers to the dinosaur age, bringing Sulu with them to protect him from Tippy and accidentally bringing Mr. Krupp with them due to him chasing after George and Harold.
Tippy sent his smaller, younger self back in time to find out where George and Harold disappeared to. Because of this, three Tippys existed at once: "Big Tippy," "Tiny Tippy," and "Slightly Younger Tiny Tippy." They traveled back in time after George and Harold, during which Tiny Tippy and Slightly Younger Tiny Tippy decided they didn't like being bossed around, so they snuck out and traveled through time to get the Goosy-Grow 4000 (ironically causing role reversal between the boy who often noticed the events and his mother who was skeptical about them). Tiny Tippy had Slightly Younger Tiny Tippy use it to restore him to his normal size and then again to make him bigger, calling himself "Supa Mega Tippy." However he refused to use the Goosy-Grow 4000 on Slightly Younger Tiny Tippy and immediately traveled back to the Mesozoic Era.
Meanwhile, Big Tippy fought Captain Underpants, discovering that water turns him back into Mr. Krupp. Then Supa Mega Tippy appeared (with Slightly Younger Tiny Tippy aboard his robot unseen). Big Tippy told his bigger self about Captain Underpants's weakness, but they argued over who should destroy him, resulting in Big Tippy activating the timer of a nuclear bomb on his robot in an attempt to kill Captain Underpants himself. Even though the bombs couldn't be turned off, he didn't care as long as it killed his nemesis. Supa Mega Tippy traveled into the future with the others after kicking Big Tippy to Mexico before the bomb exploded, killing Big Tippy along with the dinosaurs.
Supa Mega Tippy and the others traveled to the caveman age, where Slightly Younger Tiny Tippy tampered with his giant counterpart's freeze beam so that it couldn't be turned off. Supa Mega Tippy ties up Mr. Krupp under a waterfall after George and Harold got away by distracting him and cutting apart the mechanical arms. George and Harold got the cavemen to help fight against him, causing damage to him and his robot, so Supa Mega Tippy tried to freeze them, but as his freeze beam wouldn't turn off(which was due to Slightly Younger Tippy sabotaging the device and its emergency shutoff), and Slightly Younger Tiny Tippy permanently turned the Goosy-Grow 4000 on with the help of some gum to repeatedly increase his size until he accidentally drops it. This causes the Goosy-Grow 4000 to zap the ice, which causes the ice to rapidly spread across the planet, starting the Ice Age and freezing Supa Mega Tippy to death. George and Harold untied Mr. Krupp and turned him into Captain Underpants, who moved the cavemen to a safe area but was turned back to Mr. Krupp by Slightly Younger Tiny Tippy, who took him, George, Harold, Crackers, and Sulu, and traveled thirty years into the future from their time.
George and Harold turned Mr. Krupp and his future counterpart into Captain Underpants, who beat up Slightly Younger Tiny Tippy. When it looks like they would win, Tippy activates his nuclear bomb which he modified to destroy the entire galaxy. Crackers and Sulu got on board his robot and sent it back in time to before the universe existed. In the darkness, the bomb exploded, killing Slightly Younger Tiny Tippy and creating the universe with the Big Bang (or "Big Ka-Bloosh Theory").
Thus, all three of his deaths caused the major events of the universe to take place.
The Professor only made two short cameos in this novel. First in the introduction comic, and the part when Melvin, Captain Underpants, George, and Harold arrive in the present. However in that part, he was only seen from behind.
Professor Poopypants is the main antagonist of the film. He gets revenge on Captain Underpants, George Beard, and Harold Hutchins for defeating him. His new name Tippy Tinkletrousers was a joke he made up and he fakes his death in his last book).
Professor Poopypants is first seen looking at a poster advertising a position for a science teacher at Jerome Horowitz Elementary School, and says it would be the perfect cover for his plan.
The next day, he shows up at the school and is interviewed and hired by Mr. Krupp (who is really Captain Underpants disguising as him). When he starts teaching class that day, he asks the students what they would like to change about the world, which leads to him telling the students that if he were to change the world, he would get rid of laughter. Then, he shows the children a diagram of the parts of the brain, with emphasis on the Hahaguffawchucklealamus, the part of the brain where laughter comes from. After this, George asks Professor Poopypants what the P stands for in his name. When Professor P says it is private, George thinks that his name is actually "Professor Privates", which angers Professor Poopypants and makes him send George and Harold to the principal's office.
Later in the day, Professor Poopypants is walking to the cafeteria when he sees two girls in the hallway. He asks them where the cafeteria is, but they laugh at him, so he locks them in a cage. When he walks into the cafeteria, children laugh at him when he enters because George and Harold have made a comic about him entitled Captain Underpants and the Perilous Plot of Professor Poopypants. Professor Poopypants then hyperventilates over the children laughing at him, which makes him flashback to the time he presented his invention, the Sizeirator 2000 at the Nobel Invention Prize ceremony.
During the ceremony, Professor P. uses his Sizeirator to smallify a car and largify a hot dog. A lady then presenting the award isn't sure if his name is really Professor Poopypants. After his name is revealed, the audience laughs at him, causing Professor Poopypants to get mad, and state that if it weren't for his silly name, he would get to do a lot of things, like "be on talk shows", "date models twice his size", and "protect baby seals". However, the lady asks him to accept the award, but Professor Poopypants refuses and shrinks her. After the lady asks him to accept the award once again, but he yells at her to build her own invention to return herself back to normal. He then realizes he was talking out loud and asks how much of his rant was out loud.
Professor Poopypants is a short man with a large grey puff of hair. He has a mustache. He wears semicircular glasses. He also wears a purple shirt with a blue bow, blue trousers, and black shoes.
He planned to solve the Earth's hunger and trash problems but then he planned to shrink the entire planet for laughing at his silly name. He failed and was hauled off to jail. He changed his name in a failed attempt to stop other people from making fun of it, which only made things worse. He later escapes from jail to get his revenge on George, Harold and Captain Underpants, but ultimately triggered a chain of event leading up to several major events in the Earth's geological history, as well as his own death three times.
- According to his resume in the film, his birthday is on April 1, 1953, likely as a hint since April 1st is April Fools' Day, and it could be an indirect reference to him being a fool.
- Pippy is a hero in the book series, but a villain in the movie. He performs a Heel Face Turn at the end of the fourth book. But at the start of the ninth book, he betrays George and Harold by arresting them for their crimes.
- He was the only character in the film to have his name changed from his book counterpart. In the movie, his full name is Professor Pee-Pee Diarrheastein Poopypants Esquire (as his name Tippy Tinkletrousers was a joke and he was faking his death). In the whole universe, his full name is Professor Pippy Pee-Pee P. Diarrheastein Poopypants, Esq.
- He is similar to Dr. Andonuts from Earthbound by Shigesato Itoi from Nintendo in appearance.
- He bears similarities to Superman's archenemy, Lex Luthor. Both of them are intelligent scientists that though without superpowers are typically a threat to their foes.
- He also bears similarities to Brainiac, as he possesses a shrink ray that he uses to shrink Jerome Horwitz Elementary.
- If Pippy followed the name changing board, his name would be Doofus Hamsterfanny.
- Professer Poopypants doesn't appear in the series The Epic Tales of Captain Underpants.