The museum animals/people come to life because of a gold Egyptian relic. Cecil, Gus and Reginald (Van Dyke, Rooney and Cobbs) plan to steal the relic because it makes them "come alive" (feel younger), and it will in the future help them move to a retirement home. Larry (Ben Stiller) unites the museum characters to track down the thieves. Atilla the Hun and Civil War soldiers capture Gus and Reginald. Cecil escapes in the stagecoach. Pharaoh Ahkmenrah and Nick ride the T-Rex, while Larry borrows Teddy Roosevelt's horse and together they chase, corner and capture Cecil in the city park. Pharaoh Ahkmenrah uses his authority with the relic to make all the animals return to their position in the museum. Larry is about to be fired for the huge mess at the museum, but is rehired when T-Rex tracks and other signs from the previous night's chase give the museum a lot of publicity.