Plot

The prehistoric family the Croods are challenged by a rival family the Bettermans, who claim to be better and more evolved.

Still searching for a place to settle down after the cataclysmic events of The Croods (2013), the overprotective prehistoric patriarch, Grug, leads his family to the great unknown. Hoping for the best in an increasingly dangerous world, while trying to come to terms with Eep and Guy's budding romance, Grug stumbles upon a secluded Eden of plenty, containing everything that they have been seeking. However, there is a catch. This verdant heaven on Earth is already occupied by the significantly more evolved Bettermans: Phil, Hope, and their daughter, Dawn. Now, as tensions boil over between the antagonistic clans, a new menace threatens the future of both families. Can the Croods and the Bettermans put aside their differences to fight the common enemy, and live to tell the tale?—Nick Riganas

Set in prehistoric times, a family do everything that they can do in order to survive with the help of another family. Together, they set off on an adventure to find a great place to live and grow. Along the way, they face the challenges of the prehistoric world.—RECB3

A flashback shows the death of Guy's (Ryan Reynolds) parents (Mom (Melissa Disney) & Dad (Joel Crawford)) when he was a child. As they drown in tar, they tell him to find somewhere called "tomorrow". He goes on a long journey and meets a young Belt (Chris Sanders) (pet Sloth) before taking him along for the ride. This eventually leads up to events of meeting Eep (Emma Stone) and her family.

The Croods, along with Guy and their pets Chunky and Douglas, are still searching for a place to settle down, all the while surviving many dangerous creatures along the way. Grug (Nicolas Cage) is repeatedly annoyed at Eep and Guy's blossoming romance, fearing they may separate from the rest of the pack. This fear intensifies after Guy proposes to Eep that they find their own "tomorrow" without the rest of the Croods. As Grug walks off in anger, he soon comes across a giant wall and leads the whole pack to it. Behind the wall, they find endless fields filled with foods of every kind. The family has their full, until Grug notices a Banana and makes a grab for it.

But they are soon caught in a net and are released by the owners of the land, a couple called Phil (Peter Dinklage) and Hope Betterman (Leslie Mann), who were best friends with Guy's parents before their deaths and Guy's disappearance.

The Bettermans welcome the Croods to their giant tree-home as house guests, where they meet their daughter and Guy's old friend, Dawn (Kelly Marie Tran), who immediately befriends Eep. Life with the Bettermans becomes degrading for Grug as the Bettermans soon reveal themselves to be technologically advanced, better mannered, and visibly condescending toward the Croods. Believing that Guy is better off with them (They see Guy as a prospective mate for Dawn, whom they were afraid would be alone as she grew up) they hatch a scheme to get Guy to leave the Croods (They noticed that Guy and Eep were romantically involved). By the next morning Guy has taken a bath, has new clothes, slippers, and is super impressed with the Betterman's way of life. He is spending way more time with Dawn.

Meanwhile Dawn is totally blown away by the adventurous life of Eep and idolizes her. She thinks her parents built the wall to keep her inside, so she never has to face the outside world. Phil eventually takes Grug to his secret man-cave, a sauna-like place behind some waterfalls, where he manipulates him into believing Guy should leave the Crood's pack in exchange for Eep staying with her family. Meanwhile, Hope angers Ugga (Catherine Keener) by insulting her family's lifestyle and attempts to manipulate her (to leave their oasis and going back into the wild without Guy) like Phil, but fails. Grug comes back to Ugga and finds her livid at Hope's suggestion to leave Guy behind. Grug realizes that Phil has manipulated him, leading to Ugga and Grug's decision to leave.

When Eep discovers that Dawn has never left the inside of the wall. Relating this to the solitude she faced in her cave, Eep convinces Dawn to use Chunky to escape the land and jump their wall for a joyride that ends with a bee stinging Dawn and having her hand swell up. When Eep takes her back home, Guy, upon finding out, chides her for her recklessness, ending with him insensitively calling her a "cave-girl".

At dinner, tensions rise between the parents as well as Guy and Eep, especially when Dawn's swelling is revealed, culminating in Grug accidentally revealing his and Phil's deal. Having had enough, the Croods decide to leave in the morning, but Guy decides to stay after he and Eep have a falling out. Soon, the land is attacked by "Punch Monkeys" (monkey-sized but with human-like strength) on account of Grug and Ugga eating a bunch of bananas the Bettermans hoard around their land and have forbidden Grug from eating. Phil reveals he sends the Punch Monkeys the bananas every day so that they leave the Bettermans alone and since Grug and Ugga ate them, the Punch Monkeys become upset and kidnap Grug, Phil, and Guy and take them to their homeland.

As the men are taken, the remaining Croods (Thunk Crood (Clark Duke), a cave boy and Grug's son + Gran (Cloris Leachman), an old cave-woman who is Ugga's mother + Sandy Crood (Kailey Crawford), a cave girl and Grug's 5-year-old daughter) and Bettermans leave to rescue the men, but eventually get marooned on an island full of Wolf-Spiders, wolves with the characteristics of arachnids. During their time together, Hope finally snaps, lashing out on the Croods and running off.

However, during an encounter with the Wolf-Spiders (Hope gets trapped in a cave with wolf-spiders and Eep saves her. The ladies prepare for the attack, but Dawn figures out that the spiders were just protecting their cub and once the cub is united with its mother, they retreat), she learns the error of her ways and accepts the Croods. When they learn the location of the men, they name themselves "The Thunder Sisters", after a female-exclusive clan Gran was in when she was younger.

At the Punch Monkey home, Grug, Guy and Phil soon discover that Phil's diversion of a river to irrigate his farm unknowingly deprived the Punch Monkeys of their water supply and that the Punch Monkeys need the bananas not only to eat, but to offer to a large primate monster called the Spiny Mandrilla in hopes of appeasing it. The Punch Monkeys make Grug and Phil fight gladiator-style to see who the sacrifice will be and when they wear each other out, they exchange their bitter feelings with each other, making Guy regret what he said during his and Eep's fallout.

Soon, the Punch Monkeys dress all three men as bananas to sacrifice to the giant Spiny Mandrilla. Grug and Phil apologize for their poor behavior, and for putting pressure on Guy, but just as they are about to be eaten, the Thunder Sisters show up to rescue them. A long and perilous battle ends with Guy and Eep on a giant skull-chandelier where they reconcile and use it to defeat the Spiny Mandrilla by using fire to sever the ropes and send the skull falling into the abyss below. The Spiny Mandrilla climbs back out of the depths and grabs Eep by her "peanut toe", which she uses as a prosthetic Phalange, and pulls it off, sending the monster plummeting to its demise and allowing the families to escape.

With their differences finally settled, the Bettermans allow the Croods to live in their land as neighbors, with Guy realizing that Eep is his "tomorrow". Guy and Eep soon move into one of the Bettermans' bedrooms together, which Grug approves of, and the Punch Monkeys become their next-door neighbors.