Animated adventure sequel that follows prehistoric patriarch Grug as he attempts to lead his family to safety.

On their travels they discover a secluded land where they think they can be happy, but the problem is it is already occupied.

The Betterman family have been living comfortably in this new land so when Grug and his clan threaten to ruin their idyll, tensions form.

Can the two families put aside their differences when an even bigger threat occurs?