When the Bettermans invite the Croods to join their family game night, two things become clear: Phil needs to win and Grug hates to lose.

Sandy is finally old enough to join Grug and Eep for the annual Daddy Daughter Day and Grug couldn’t be more excited. But when Sandy struggles to fit in with Grug and Eep’s traditions, Grug has second thoughts.

Guy is always surprising Eep with romantic gestures and Eep wants to return the favor. But when Guy proves impossible to surprise, Eep has to step up her game.

After Thunk and Guy tell Eep and Dawn a campfire story of Gorgwatch, a hideous monster who roams the woods, the girls are terrified.

When Grug overhears Thunk accidentally call Phil "Dad", he tries to reconnect with Thunk by taking him to the natural spectacle known as "Big Shine."

When the adults exclude the kids from their adult-only cave, the kids make their own much cooler cave, soon making the adults want to switch caves.

When Grug saves Hope's life during a dangerous mountainside tartichoke harvest, rather than feeling grateful, Hope is desperate to save Grug's life in order to not be indebted to him.

Each kid believes that they have the best pet on the farm, and hold a contest to prove it. Meanwhile, Phil's attempts to find a pet to enter proves dangerous, as he turns to wild animals.

Grug accidentally reveals a subterranean cave beneath the treehouse. When Phil can't convince Hope, Grug, and Ugga that the treehouse is more impressive than the new cave, he sets out to destroy the cave.

An attempt to fix a broken vase leaves Guy and Hope stuck together with glue. Guy's ability to stay calm is tested when Phil is too busy to help, and the other farm residents also get stuck.

Thunk goes missing after the Thunder Sisters dismiss his help during a battle. The Thunder Sisters, and Grug, Phil, and Guy's newly formed "Thunder Sifters" search on and off the farm for Thunk.