Larry Daley is divorced, unable to keep a steady job, and has failed at many business ventures including his dream job of being an inventor. His ex-wife fears his lifestyle is a bad influence on his eleven-year-old son Nick. One day, an elderly nigh security guard at the American Museum of Natural History hires Larry as an intern, planning to let him take over after he retires. The one thing he fails to tell him is that because of an ancient Egyptian artifact being kept in the museum, all of the museum's exhibits come to life at night after the museum closes. He is told by a living wax figure of Franklin Roosevelt, that the exhibits come to life because of the artifact, and if any are outside the museum at dawn, they turn to dust. On the night Larry brings Nick to the museum, the exhibits fail to come to life and Larry discovers that the artifact was stolen. He later finds the museum's old curator, Cecil and his friends have stolen the artifact and plan to frame him for its theft.