Captain Underpants and the Invasion of the Incredibly Naughty Cafeteria Ladies from Outer Space (and the Subsequent Assault of the Equally Evil Lunchroom Zombie Nerds)

Captain Underpants and the Invasion of the Incredibly Naughty Cafeteria Ladies from Outer Space (and the Subsequent Assault of the Equally Evil Lunchroom Zombie Nerds) is the third book of the "Captain Underpants" series by Dav Pilkey. The series of American children's books are about two fourth graders, George and Harold, and their mean principal Mr. Krupp, who can turn into Captain Underpants. It was published on September 1, 1999. It is the first book to feature the use of 'Extra-Strength Super Power Juice' (an invention of Zorx, Klax, and Jennifer, the antagonists of the book), which is used to give Captain Underpants superpowers later in the book.
Plot.
Zorx, Klax and Jennifer, three evil extraterrestrials, land on the rooftop of Jerome Horwitz Elementary School, but nobody is aware that their spaceship is on the roof of the school. Meanwhile, George and Harold mess with their science teacher, then make the cafeteria ladies a fake recipe, disguised as "Mr. Krupp's Krispy Krupcakes" for Principal Krupp's "birthday". The lunch ladies decide to surprise Mr. Krupp and make cupcakes for the entire school and the school is flooded with green goop. The next day, the lunch ladies tell Mr. Krupp about the mess, who gets very mad when he hears that they did it for his birthday. ("But it wasn't even my birthday!") Furious, the lunch ladies blame George and Harold, but Mr. Krupp needs proof to punish them. Furious from past harassment by the two boys, the lunch ladies quit. About 10 seconds after, the aliens come in, very badly disguised as humans and Mr. Krupp hires the three, unaware that they're actually bloodthirsty alien invaders in disguise as humans. For the boys' antics, Mr. Krupp forces them to eat their lunch in his office where he can keep an eye on the two boys, much to the boys' surprise. The next day, while Mr. Krupp has a banana, both boys have their own weird sandwiches and other food so junky, Mr. Krupp feels like he'll get sick and exits his office for some fresh air.
After their lunch, George and Harold go off to change the letters on the sign in the cafeteria, only to find out that the sign is already changed by the aliens. They immediately notice that all of the students and staff at the school have become evil zombie nerds. Sneaking into the lunchroom, George and Harold learn that the aliens plan to feed the zombie nerds growth juice, turning them into giant minions bent on taking over the world. George and Harold steal the carton of growth juice and pour the contents out the window, most of which lands on a dandelion, turning it into the massive Dandelion of Doom. Mr. Krupp doesn't believe them, but starts to believe them after Miss Anthrope takes a bite out of his desk. When Harold escapes Zorx's grasp, he pulls off his gloves in the process. Zorx snaps his tentacle at them, turning Mr. Krupp into Captain Underpants, who runs to the shoe store for what the incredibly graphic violence chapter said.He went to the local shoe store for a cheeseburger.
The boys temporarily defeat the aliens by Captain Underpants' return, but the three escape, soon into the alien spaceship, where they steal multiple cartoned juices, before the aliens lock them in their jail cell. While the aliens gloat, the boys switch the labels of the growth and self-destruct juices, along with the spray and fuel tanks. The trio jump off the spaceship before it explodes (killing Zorx, Klax, and Jennifer). They end up landing near the Dandelion of Doom, which begins to eat Captain Underpants. George reluctantly gives some of the "Extra-Strength Super Power Juice" to Captain Underpants, who kills the dandelion with his new powers. Harold mixes the Anti-Nerd Juice with root beer, which transforms the zombie nerds back. However, as a result of the Super Power Juice, Mr. Krupp (when Captain Underpants) permanently has superpowers.
Comics.
"Wedgie Wars Episode 1: The Phantom Principal".
A parody of "", this book explains the events of the previous two books and how Captain Underpants and Mr. Krupp can change.
"The Night of the Living Lunch Ladies".
The Lunch Ladies are cleaning Friday's leftovers when the janitor locks them in the school, where they die by Sunday night. The janitor unknowingly buries them at a haunted hill. The Lunch Ladies rise from the dead and attack the gymnastics teacher. Captain Underpants came and tries to give them wedgies but it doesn't work. They get in a big fight and they all end up on a building. Captain Underpants uses the Toilet Paper of Justice to tie the ladies but they break free with the help of steak sauce. Captain Underpants then swings to safety in the toilet paper, while the lunch ladies fall to their deaths when they try to follow.
"Dog Man: The Wrath of Petey" (Full color version only).
Dog Man was the best cop of the world, but he only had one weakness. He was eating out of the garbage cans, rolling in the dead fish and sniffing the other dogs. The cops (even the chief) decided to give him a bath, but Dog Man ran away, because he doesn't like baths. The cops searched all around the city looking for Dog Man, but they couldn't find him anywhere. Soon, Petey decided that he should escape. He puts the newspaper in the toilet and he clogged the toilet by flushing the chain. The water from the toilet began going higher and higher and Petey escaped cat jail to his crime spree by robbing banks, stealing jewels and hi-jacking cars. But the cops could never catch them, they wish Dog Man would return. Meanwhile, Dog Man was hiding in an alley, eating out of a garbage can, and saw a newspaper. He felt ashamed, but he knew he must be brave and returned bravishly to stop Petey. He searched for him, picked up a trail, led straight to his house, but it was a trap. Petey sprayed water and Dog Man got scared, he ran away from Petey by digging a hole to the zoo. Dog Man came up in a cage where the skunks live and the skunks sprayed on Dog Man. Dog Man doesn't like too much stinky stuff. Petey ran out of the hole and he gets caught by a net. The cop said to Petey that he should go back to cat jail. While the cops washed Dog Man, Petey went back to cat jail. Dog Man was so clean, but then he rolled on the dead fish again. This comic was both seen on the full color version of the third Captain Underpants book in 2014 and Dog Man Unleashed in 2016.