Billy & Mandy vs. The Martians
Billy & Mandy Vs The Martians
Series The Grim Adventures of Billy & Mandy
Season 6
Production code 614
Writer Maxwell Atoms

Nina Bargiel Jeremy Bargiel

Broadcast information
Cartoon Network US Premiere March 23, 2006
Chronological information
Pandora's Lunch Box
Dumb-Dumbs & Dragons
Billy & Mandy vs. the Martians is a double length episode and is the 14th episode from season 6 of The Grim Adventures of Billy & Mandy.

Episode Summary

I have my sources
"I have my sources..."

The following contains plot details.

Grim finally gets sick of Billy and Mandy after they destroy his favorite childhood toy Fancy Jake, Grim then says he would leave Billy and Mandy if he could. Then Morg, disguise as a human tells Grim his deal with Billy and Mandy only applies on Earth. Then Morg gives Grim a card in case he really wants to leave Billy and Mandy.

Grim then travels to Mars with Morg, however he left his trunk at Billy's house, Billy and Mandy noticed this and hide inside the trunk waiting for Grim to come back for it and take it to Mars (Irwin is also in the trunk with Billy and Mandy). The trunk is put on a small space ship, when Billy, Mandy and Irwin are on the ship they accidentally fall out the ship, forcing them to walk to Morg's base. On the way they find a martian animal which helps them fight the martians by eating them, Billy names the animal Admiral Wolverine Lightning Bolt.

When Grim and Morg are settled on Mars Morg tells Grim about his martian zombie slaves and how he is the ruler of Mars, he then tells Grim they could do the same (the same thing that turned everyone to zombies) to Earth so they could rule together. Morg tells Grim they could rule Earth using the brain caster, which is a machine which can only be powered by the stupidest and most distracted of minds to turn everyone to zombies.

After that the martians invade Earth to find a person with the right brain for the brain caster. While this is happening Billy, Mandy and Irwin find their way on to Morg's base. When they do this they find out Earth has been invaded.

After a while of testing for the right brain for the brain caster Grim suggests that Morg should just find Billy and use him for the brain caster, but Morg ignores Grim and tells him he should stop thinking about Billy and Mandy. After this Morg suggests they take a break from trying to find the right brain and play a board game instead. He tells Grim to go to the door next to the one marked forbidden. Grim choose a board game, but then decides to look in the door marked forbidden as well, to his surprise he finds out they are a lot of destroyed reapers from other planets (they were destroyed for not following along with Morg's plans). Morg find Grim lurking in the room and tells him they died by accident and he should forget this room, Grim pretends to agree and makes it look like he will still work with Morg.

After this Billy, Mandy and Irwin some how take a martian space ship they go back to Earth, but when they get there they are raided by martian zombies and are taken back to Mars, so Morg can use Billy for the brain caster. Morg banished Mandy and Irwin to a pit were monstrous bugs like creatures try to eat Mandy and Erwin, however Mandy is saved by Admiral Wolverine Lightning Bolt, sadly Irwin got eaten by the monster. During this Billy talks to Grim about friendship which makes him slightly like Billy and Mandy a bit more. Grim goes to save Mandy from all the zombies and Billy overpowers the brain caster causing it to break, this makes any of the zombies that were created from Billy's brain turn back into normal people.

Grim and Mandy come back to Morg's base and try to get him to become Grim's slave however Billy sent him though a tube which chucked him off Mars and into space. Grim makes back up with Billy and Mandy and Irwin comes back stinking and with flies flying around him, Mandy asks how he survived because she saw him get eaten and he replies don't think about it too hard.

The Ending came, when we see Billy and Irwin stuck on Mars wearing nothing but their underpants and one sock each (Billy with one sock on his right foot and Irwin with one sock on his left foot), Billy and Irwin get attacked but an orange furry monster.


  • Story by: Maxwell Atoms and the Bargiel Brothers
  • Storyboard by: John Bahn and Mike Diederich
  • Directed by: Juli Hashiguchi and Eddy Houchins


  • Morg: You! But I fought... But how?

  • Ledge: I'm Ledge!
  • Irwin: (Screams)
  • Ledge: (Screams)

  • Mandy: I was wondering when you showed up.
  • Grim: Look out!

  • Mandy: I know you come back to us, Grim.

  • Billy: Admiral Wolverine, where have you been?

  • Irwin: Here I am.

  • Mandy: But I saw the beetle swallow you how did you escape?


  • While inside Grim's Trunk, Billy stats that it's bigger on the inside, as a reference to the TARDIS from Dr. Who.
  • It is revealed that there is actually more than one reaper in the universe. Apparently, every planet in the solar system has its own reaper i.e. a Martian reaper).


Billy & Mandy vs. the Martians/Gallery


Billy and Mandy - S6E08 - Billy & Mandy vs the Martians23:00

Billy and Mandy - S6E08 - Billy & Mandy vs the Martians

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