Luigi's Mansion: Dark Moon is an action-adventure video game developed by Next Level Games and published by Nintendo for the Nintendo 3DS. It is the sequel to the 2001 Nintendo GameCube game Luigi's Mansion. It is also the third video game where Luigi is the main character instead of Mario after the first Luigi's Mansion game and Mario is Missing!.

In Dark Moon, the player controls Luigi, who is equipped with the Poltergust 5000, a specialized vacuum cleaner used to capture ghosts. In the game's single-player mode, the main goal is to retrieve the shards of the shattered Dark Moon, a magical object that has a pacifying effect on the ghosts who live in the game's setting, Evershade Valley, while also rescuing Luigi’s brother, Mario, from King Boo, the mastermind behind the disappearance of the Dark Moon and the paranormal activity. Luigi progressively explores five different-themed mansions while capturing ghosts and solving puzzles in order to progress to the next level. Dark Moon offers a cooperative multiplayer mode that can be played locally or online via Nintendo Network. The game received generally positive reviews from critics, praising the game’s 3D visuals and new features, but some criticism was given for the game's mission-based structure and lack of checkpoints.