《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。

沒想到世界末日突然降臨，山洞被毀，一家人被迫離開家園，展開一場全新的旅程。離開了居住了“一輩子”的山洞，展現(xiàn)在他們眼前的是一個嶄新絢麗卻又充滿危險的新世界，到處都是食人的花草和叫不出名字的奇異鳥獸，一家人遇到了全所未有的危機。在旅途中，他們還遇到了游牧部落族人guy，他有著超凡的創(chuàng)造力和革新思想，幫助咕嚕一家躲過了重重困難，途中他還發(fā)明了很多“高科技”產品，并讓他們知道了原來生活需要“用腦子”，走路需要“鞋子”等等。一行人在影片中展開了一場鬧騰而又驚險的旅程。

瘋狂原始人經(jīng)典英語臺詞：

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 pretty 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."