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The Grim Adventures of Billy & Mandy

Which Came First?

E16    Jul 30, 2004    TV-Y7
While going to a science museum, Billy and Mandy's school bus breaks down in the middle of the desert. After digging for fossils, Billy, Mandy and Grim wander around and find an abandoned mine, where Billy is captured by a giant, mutant chicken. When Mandy and Grim go to rescue him, they find an underground laboratory from the days of the Cold War where mutant chickens were created. The mountain makes eruption, the chickens are roasted by lava, and the whole class obtains food so they do not have to resort to cannibalism.
Where to Watch Which Came First?
Cast of Which Came First?
  • Greg EaglesGrim (voice)
  • Richard Steven HorvitzBilly (voice)
  • Grey DeLisleMandy (voice)
  • Vanessa MarshallIrwin (voice)

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