The game takes place in a haunted mansion, which Luigi won in a contest he did not enter. He told his brother to meet him there to celebrate his victory. Luigi is searching for his brother Mario, who came to the mansion earlier, but went missing. To help Luigi on his quest, an old professor named Elvin Gadd has equipped him with the "Poltergust 3000", a vacuum cleaner used for capturing ghosts, and a "Game Boy Horror", a device used for communicating with Gadd.
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