With Nicholas Cage setting the scene as Grug, the overprotective father living in a cave with his wife (Catherine Keener), pesky mother-in-law (Cloris Leechman), and three children, his oldest daughter Eep (Emma Stone) is ready to venture forward exploring on her own. It isn’t until Eep discovers Guy (Ryan Reynolds) that her father’s word becomes questionable.
Soon Grug struggles for acceptance by the clan that used to belong to him–his family. Eep’s father sees the success in trying new approaches through the gentle coaxing of his daughter, and in desperation he conforms to non-conforming with the help of Guy, the Neanderthal inventor.
This is a great way for kids to realize in order to progress, risk must be taken, otherwise they are destined for destruction.