The Grim Adventures of Billy and Mandy Wiki

Runaway Pants
Runaway Pants Title Card.png
Series The Grim Adventures of Billy & Mandy
Season 5
Production code 509
Writer Maxwell Atoms

Alex Almaguer

Broadcast information
Cartoon Network US Premiere June 28, 2005
Paired with Scythe 2.0
Chronological information
Puddle Jumping
Scythe 2.0

Runaway Pants is the 9th episode from season 5 episode of The Grim Adventures of Billy & Mandy.


When Billy realizes that he is unable to pass the President’s fitness test at school, he asks Nergal Jr for his help by transforming into a pair of pants that whoever wears it makes them run so fast.


As the episode starts, a narrator tells the story about ‘The Billy Zone’ then the narrator explains about the characters except Mandy, who swore that if the narrator doesn’t get the camera off her face, she would kill him, after this, we meet Billy, the boy who would change a nation, just then, Billy tells Mandy if she’s ready for school, however, Mandy tells Billy to get lost. Then Irwin meets Billy and Mandy and explains that he’s been working out for the President’s fitness test and shows his strong abs, however, Mandy, not Impressed, trims a piece of Irwin’s chest hair and tells Irwin that if he does the same thing with his personality, they might have something to talk about. Just then, Nergal drops off Junior for the fitness test at school, Junior then explains the he doesn’t have to be ready because he can change his shape to make himself as muscular and as fit he needs to be. however, Mandy says that Junior’s muscular right leg is the second most disgusting thing she’s ever seen with Irwin’s muscular torso and arms being the first. Then Irwin races Junior to the bus stop as they happily race together to the bus stop. Billy wants to race too but he can’t run. Mandy tells Billy that he is out of shape, but Billy says "It isn’t true!”. As Mandy walks on Billy, the scene cuts to the school’s football field where the president’s fitness test take place. But because Filberman had a slight brush with the grim reaper this morning and is recovering at the hospital from no exercise, too many doughnuts, the grim reaper is filling in as substitute coach. as the test begins, the students in the test are suffering pain while trying to do sit ups but Mandy and Junior are the only ones not suffering pain because Mandy isn’t doing any sit ups and Junior is able to do sit ups. Billy finally did a sit up but Junior did 714 more than him. Then the students are suffering doing lift ups but Junior is also able to do 4,001 lift ups. However Billy and Mandy are the only ones not doing any lift ups because billy is still doing sit ups and Mandy is also not doing lift ups. then Billy dies when his head explodes after doing a sit up but the scene where Billy’s head explodes was just grim’s daydream, revealing that Billy’s head didn’t explode when Billy finally did a sit up. Then billy hits the showers. before the Final test: the 50-meter run, the students except Junior are pathetic at the test and Mandy is the worst of them all because she didn’t do exercise because she hates exercise. Billy is also the worse of them all because he is even more pathetic than the students at doing exercise. Billy is unable to pass the test because he is no good at running because how short his legs are but when he hears Junior tell him the he doesn’t have powers like him then he’d win for sure, Billy has an idea that he needs Junior to turn into a pair of pants that he can wear so he can win the race. Mandy was gonna say that the idea Billy has is the stupidest idea ever but she says that the idea billy has is the probably the single most brilliant idea Billy’s ever had instead. Junior’s never turned into anything besides people before but he turns into a pair of pants that Billy can wear so he can win the race for the President anyways. Before the final test starts, Grim says if the students lose, then he will cut their heads of and Irwin says “That’s messed up yo!”. Billy wins but he can stop running because Junior can’t stop running and can’t change back so Grim and Mandy decide to sell Billy’s things. Billy still can’t stop running but he becomes famous so everyone and the president love him. The Narrator continues narrating the story, as Billy and Junior kept on running. some say that they run to this very day, circling the world till the end of time. So remember, one person alone cannot make a difference. He needs a good pair of pants beside him. And what became of Grim and Mandy you ask? but before the Narrator tells what became of Grim and Mandy, Mandy suddenly came and confronts the narrator. The narrator tries to tell Mandy that he’s the narrator and that he tells the story but Mandy tells him to stop making crud up and that this stuff never happened, revealing that the entire bloody episode is false and not true. Billy, Grim, Abraham Lincoln, Junior and Irwin, who also suddenly came and confront the Narrator, agree with Mandy and Billy calls the narrator a Dirty Dirty Liar. narrator tries to tell Billy, Mandy, Grim, Irwin, Abraham Lincoln and Junior that he was just trying to entertain people but Billy, Grim, Abraham Lincoln, Irwin, and Junior beat up the narrator for embarrassing them in front of the people in the audience by telling this episode’s false story. However, Mandy covers the camera the audience use to see the episode through using a TV so they would absolutely not watch Billy, Grim, Irwin, Abraham Lincoln and Junior beat up the narrator because how Violent and inappropriate the scene where Billy, Grim, Irwin, Abraham Lincoln, and Junior beat up the narrator is that the audience cannot see, ending the episode.


  • Story by: Maxwell Atoms, Alex Almaguer
  • Storyboard by: Alex Almaguer
  • Art direction: Rae McCarson
  • Directed by: Sue Perrotto


Click here to view more images from Runaway Pants.
The image gallery for Runaway Pants may be viewed here.


  • The opening of the episode is a parody of the 1960s TV show The Twilight Zone.
  • Although the episode's story was technically made-up by the "narrator," it's true in that Junior's never actually transformed into inanimate objects.
    • During the narrator's story, Junior said he's never transformed into anything besides people, but he's also transformed into animals.



Billy and Mandy - S5E05 - Runaway Pants ~ Scythe 2.0-1