When the exhibits at New York's Natural History Museum start behaving strangely, Larry Daley (Ben Stiller) -- now the director of nighttime operations -- must find out the cause. He learns that the Tablet, which magically brings Teddy Roosevelt (Robin Williams), Jedediah (Owen Wilson) and the other exhibits to life at night, has started to decay. Larry, along with his son and museum friends, must travel to London's British Museum to learn how to prevent the Tablet's magic from disappearing.