Invader ZIM is an eccentric alien soldier from the planet Irk. He was banished from the Irken Empire to food-courtia after nearly destroying his home planet on an early mission(Impending Doom 1). After begging his superiors, the Almighty Tallest Red and Purple, for another chance, they decide to get rid of him once and for all. They trick him into going on a "secret mission" to an obscure planet at the edge of the universe, a planet with the unlikely name of Earth. Their trick works, and now ZIM is intent on bringing down the human race. He disguises himself as a schoolboy, and now the only person who can stop him is one kid - Dib, a somewhat insane paranormal researcher, who sees straight through ZIM's disguise and is intent on stopping his reign of "doom". The only problem is neither of them are very smart.
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