Day of the Tentacle, also known as Maniac Mansion II: Day of the Tentacle, is a 1993 graphic adventure game developed and published by LucasArts. It is the sequel to the 1987 game Maniac Mansion. The game's plot follows Bernard Bernoulli and his friends Hoagie and Laverne as they attempt to stop the evil Purple Tentacle—a sentient, disembodied tentacle—from taking over the world. The player takes control of the trio and solves puzzles while using time travel to explore different periods of history.
Dave Grossman and Tim Schafer co-led the game's development, their first time in such a role. The pair carried over a limited number of elements from Maniac Mansion and forwent the character selection aspect to simplify development. Inspirations included Chuck Jones cartoons and the history of the United States. Day of the Tentacle is the eighth LucasArts title to use the SCUMM engine.