At the end of The Lego Movie, the Lego characters' world was invaded by Duplo figures. Now the Duplo invasion continues, as these strange alien creations smash their way through Bricksburg, making it impossible for the citizens to rebuild. It's up to Emmet and his friends to figure out what the things from Planet Duplo want, and how to stop them. Can they find common ground, or does it have to be all-out war?