《瘋狂原始人》是講述一個原始人家庭冒險旅行的3D喜劇動畫片。原始人咕嚕一家六口在老爸Grug的庇護下生活。每天搶奪鴕鳥蛋為食，躲避野獸的追擊，每晚聽老爸敘述同一個故事，在山洞里過著一成不變的生活。大女兒EEP是一個和老爸性格截然相反的充滿好奇心的女孩，她不滿足一輩子留在這個小山洞里，一心想要追逐山洞外面的新奇世界。
《瘋狂原始人》經典臺詞
Guy: This is called a brain. I think that's where ideas go.
Thunk: Dad, I don't have a brain.
"Eep: My name's Eep and this is my family, the Croods. We never had the chance to explore the outside world because of my dad's one rule:
Eep: Never leave the cave.
Grug: New is always bad. Never not be afraid!
Eep: We never had a chance to explore the outside world, but what we didn't know was that our world was about to change."
"[Gran tries to eat Belt, the sloth, but Belt pulls a knife on Gran.]
Guy: Don't do that. He's not food. He's a pet, my pet.
Gran: What's a pet?
Guy: An animal you don't eat
Gran: We call those children.
Eep: [Smitten with Guy] Isn't this fun? We're taking our first trip together."
"Grug: Just think, our whole family packed together on a long, slow trip across country. We'll tell stories. We'll laugh. We'll become closer as a family.
[Sandy, the baby, bites Grug's face.]
Grug: Ah, get her off!
Ugga: If you're not ready to challenge her then don't look her in the eye!
Gran: Could you keep your big giant arms on your side of the trail?!
Grug: You want me to turn this family around? Do you? Because I will turn this family around so fast!
Thunk: Dad, I gotta go!
Grug: Come on, you can hold it.
Gran: I'm not dying on an empty stomach.
Ugga: Ugh, we're all Ptty tired.
Grug: We'll eat when we get there.
Gran: It's taking too long! I'm grabbing a snack."
"Guy: We've gotta move faster. I call them shoes.
Eep: [screams] I love them! Where are my feet?"
"Eep: Oh, I've been in that cave forever!
Grug: Three days is not forever.
Eep: It is with this family.
Ugga: Mom, we're ready to leave. Mom?
Gran: Still alive!
Grug: It's still early."
"Grug: Ideas are for weaklings."
"Guy: Who are you.
Eep: OH! Eep.
Guy: Let me clarify Eep. The world is ending.
Eep: What
Guy: I am calling 'The End'"
"Guy: I am guy.
Eep: Guy.
Guy: And this is Belt.
Guy: Cook, conversationalist, navigator.
Guy: Also keeps my pants up.
Eep: What are pants up."
"Guy: Belt, emergency idea generator activate!"
"Grug: Never not be afraid."
"Thunk: You need a name, I think I'll call you Douglas. Roll over Douglas."
