Plot

Set at the dawn of time, when prehistoric creatures and woolly mammoths roamed the earth, Early Man tells the story of Dug, along with sidekick Hognob as they unite his tribe against a mighty enemy Lord Nooth and his Bronze Age City to save their home.

An asteroid collides with the prehistoric Earth, causing the extinction of the planet's dinosaurs, but sparing a tribe of cavemen living near the impact site. Finding a roughly spherical chunk of the asteroid that is too hot to touch, the cavemen begin to kick it around and invent the game of football. Many years later during the Stone Age, a young caveman named Dug (Eddie Redmayne) lives in the village with the chief Bobnar (Timothy Spall) and many other cavemen such as Asbo, (Johnny Vegas), Gravelle (Gina Yashere), Treebor (Richard Ayoade), Magma (Selina Griffiths), Barry (Mark Williams), Grubup (Richard Webber), Thongo (Simon Greenall) and Eemak (Simon Greenall). One day, Dug suggests to Bobnar that they should try hunting woolly mammoths instead of rabbits, but Bobnar brushes him off..

An asteroid collides with the prehistoric Earth in the Neo-Pleistocene age, causing the extinction of planet's dinosaurs, but sparing a tribe of cavemen living near the impact site. Finding a roughly spherical chunk of the asteroid that is too hot to touch, the cavemen begin to kick it around and invent the game of football, near modern day Manchester. Cave paintings were made of the cavemen playing football.

Many years later during the Stone Age, a young caveman named Dug (Eddie Redmayne) lives in the village with the chief Bobnar (Timothy Spall) and many other cavemen such as Asbo (Johnny Vegas) (a fidgety member who often says "Champion"), Gravelle (Gina Yashere) (an injury-prone member), Treebor (Richard Ayoade) (a large and cowardly member of Dug's tribe), Magma (Selina Griffiths), Barry (Mark Williams) (isn't bright and has a rock friend named Mr. Rock), Grubup (Richard Webber) (a hungry member who will eat anything), Thongo (a strong and silent member who mostly responds with a grunt), and Eemak (Simon Greenall) ( a warm and funny member who the other tribe has trouble understanding). The whole tribe lives in the crater created by the asteroid, which is the only fertile piece of land, surrounded by desolation poke marked by volcanoes and barren wasteland.

One day, Dug suggests to Bobnar that they should try hunting woolly mammoths instead of rabbits, but Bobnar brushes him off as mammoths weigh 5 tons and have bone crushing strength. Bobnar argues that even their ancestors did not hunt big things, but always went after little round things. The tribe is fully incompetent and cannot even manage to hunt down a rabbit. Eventually, the tribe gets lucky as the rabbit runs into Mr. Rock and falls unconscious.

A Bronze Age army of War Mammoths (a fighting machine made up of bronze, powered by a mammoth underneath a protective armor) led by Lord Nooth (Tom Hiddleston) drives the tribe out of the valley and into the surrounding volcanic badlands, proclaiming that the Stone Age has ended, and the Bronze Age has begun. Nooth had attacked the valley as he wanted to mine it for the ore.

Dug tries to attack the army but falls into a cart and is unknowingly taken to Nooth's city. Dug regains consciousness inside the Bronze city and sees an entire civilization built around bronze. While trying to evade the guards and escape he enters the back rooms of an arena. Dug is mistaken for a football player and led onto the pitch before a full stadium crowd. As Dug is thrust into the game, he realizes that football is the game that his ancestors used to play and the cave paintings he saw referred to this. Dug is discovered as an impostor, after he scores an own goal.

Dug challenges Nooth's elite local team (led by captain Jurgend (Kayvan Novak)) to a match with the valley at stake and promises that the tribe will work in Nooth's mines forever if they lose. Nooth dismisses the proposal at first but changes his mind once he realizes that he can profit from the match. Turns out Nooth is acting without the knowledge of Queen Oofeefa.

Dug discovers that although his ancestors invented football, the other members of his tribe are too dim to understand it. Dug tells his chief that they have to win the game of football to get their valley back. Dug takes time to explain the game and its rules to the members of his tribe. Hognob, Dug's pet boar, is not allowed to play as he is not human. Their only ball is destroyed (which he brought with him from Bronze City), by a giant man-eating duck, who was provoked by Grubup who was hungry. Bobnar tells Dug to give up and says that the tribe is still together, and they can survive in the badlands. But Dug is adamant that the team can still win. Dug and his pet boar Hognob (Nick Park) sneak into the city to steal more but are found by a resident named Goona (Maisie Williams) (a tomboyish vendor and football enthusiast in the Bronze City). Resentful over the team's exclusion of women, she helps them steal some balls and agrees to coach the cavemen.

Goona points out that the players on Nooth's team are talented but too egotistical to work together effectively. The cavemen improve in skill and teamwork under her coaching. Nooth receives a Message Bird (Rob Brydon) from Queen Oofeefa, warning him to not underestimate Dug's team as the consequences of losing the match to cavemen would be catastrophic. To demoralize Dug, Nooth has him brought to the mines and shows him cave paintings made by his tribe's ancestors, who proved so inept at football that they never won a match and eventually gave up the sport.

On the day of the match, with Queen Oofeefa (Miriam Margolyes) in attendance, Dug announces his forfeiture as part of a deal to spare the rest of the tribe and agrees to take their place in the mines. However, his reinvigorated teammates persuade him to break the deal and play the match. They are down 3-1 at half-time, but rally in the second half to tie the score. Nooth incapacitates the referee Dino (Kayvan Novak) (also Lord Nooth's second in command) and takes his place, making biased calls in favor of the local team that leads to Bobnar (the cavemen's goalkeeper) being knocked out.

Hognob takes his place and blocks a penalty kick and Dug scores using a bicycle kick to win the match for the cavemen, 4-3. The cavemen win their village back with the respect of Oofeefa, the local team, and the crowd. Nooth tries to escape and steal the crowd's admission money, but Goona stops him with help from a giant duck; Nooth is arrested for his crimes, and everyone gets their money back.

Goona and Nooth's elite local team join Dug's tribe for a hunt, but they are chased away by a rabbit pretending to be a woolly mammoth.