The second comic in the book starts with an introduction about Underpantyworld, Captain Underpants' fictional home world. It is explained that this planet is very peaceful and the residents wear only underwear. One day, the Wedgie Warlords aboard the Starch Ship Enterprise suddenly appear and spray starch on Underpantyworld. However, the leader, "Big Daddy Long Johns", creates an amulet that is able to protect the entire planet from the starch. Unfortunately, he accidentally drops into the mouth of his son, "Little Baby Underpants" (a.k.a. Captain Underpants), so the entire planet becomes doomed. Big Daddy Long Johns and his wife, "Princess Pantyhose", are forced to save their son, and not the planet since it is obvious their planet is a goner. By stretching his underwear, Big Daddy Long Johns and Princess Pantyhose catapult Little Baby Underpants towards Earth, while Underpantyworld is destroyed. Little Baby Underpants is adopted by two old people, who name him "Captain", after their favourite cereal. Unfortunately Captain just doesn't fit in with other kids (because he doesn't wear clothes like the others). Then one night Captain has a dream, where he meets his birth parents. They explain he is not an ordinary person, he is a superhero guy and because he has the amulet still inside of him, he is invunerable to starch. They explain all he has to do was to shout the sentence "I summon the power of Underpantyworld", and he will overcome the powers of starch. Captain Underpants what they mean and thanks them. He wakes up and becomes a superhero named Captain Underpants, and never became afraid of starch anymore. The comic ends and in the real world, Captain shouts out the sentence.
- This comic parodies Superman's story, where Krypton's destruction forced his parents to send him to Earth.