Gretta, a budding songwriter, finds herself alone after her boyfriend Dave ditches her. Her life gains purpose when Dan, a record label executive, notices her talent.

The prehistoric Croods family live in a particularly dangerous moment in time. Patriarch Grug, his mate Ugga, teenage daughter Eep, son Thunk, and feisty Gran gather food by day and huddle together in a cave at night. When a more evolved caveman named Guy arrives on the scene, Grug is distrustful, but it soon becomes apparent that Guy is correct about the impending destruction of their world.