Circa 10,000 BC, a hunter-gatherer tribe called the Yagahl live in the Ural Mountains and survive by hunting woolly mammoths. The tribe is led by a hunter who has killed a mammoth single-handedly and earned the White Spear, and venerate Old Mother, an elderly woman with shamanistic powers. The mammoths begin to dwindle, and the village chief finds a young girl named Evolet who survived a massacre of her village, perpetrated by what Old Mother calls "four-legged demons" who will come when "the Yagahl go on their last hunt". She prophesies that whoever kills the leader of the "demons" will win both Evolet and the White Spear, becoming the next village chief. The tribe believe that the "demons" are mammoths, whose return will save them from starvation. The chief, however, does not believe the prophecy and leaves to find another way to save his people. He entrusts the White Spear, his son D'Leh, and the true purpose of his quest to his friend Tic'Tic. The rest of the tribe, including D'Leh's rival Ka'Ren, believe that D'Leh's father was a coward and fled. Over time, D'Leh and Evolet fall in love.
When the mammoths finally return, D'Leh hunts them with the men of the tribe under Tic'Tic's leadership, and manages to kill one by accident, inadvertently winning both the White Spear and marriage to Evolet. The village believes Old Mother's prophecy is coming true, but D'Leh is consumed by guilt for not earning the White Spear fairly. After speaking with Tic'Tic, he gives up the White Spear, forfeiting his marriage to Evolet. The next day, horse-raiders attack the camp, enslaving Evolet and several others and killing many of the tribe. D'Leh, Tic'Tic, Ka'Ren and young boy Baku set out to rescue their fellow Yagahl, but Evolet is recaptured with Ka'Ren and Baku during an attack on the slavers by terror birds, and Tic'Tic is wounded. While hunting, D'Leh falls into a pit, where he rescues a Smilodon before escaping himself. After Tic'Tic recovers, they make their way to a village and learn of a prophecy from the Naku, another tribe; whoever talks to a Smilodon they call the "Spear-Tooth" will help free their people. D'Leh realizes the prophecy is about him when the Smilodon he rescued arrives and refuses to kill him. They also learn that D'Leh's father was a guest of the Naku until he was captured by the slavers and Tic'Tic finally reveals to D'Leh why his father left.
Several tribes form a coalition to pursue the raiders with D'Leh as their leader. They find the ships holding Evolet and their families but with no means to follow, they journey through a desert and discover an advanced civilization, ruled by an enigmatic god-king known as the "Almighty", the last of a group of people who had survived the collapse of an advanced civilization from across the sea. Here it is discovered that the kidnapped Yagahl work as slaves. The warlord who kidnapped Evolet tries to coerce her into loving him, only to be arrested by the Almighty's priests when they find he has taken her without permission. During a night scouting raid, D'Leh learns of the Almighty and the fate of his father, who perished as a slave. The party is spotted by the guards, who are killed by Tic'Tic before he succumbs to his wounds. The Almighty's priests believe that Evolet is destined to kill The Almighty, based on the whip scars on her hands matching the stars they call the "Mark of the Hunter" and an ancient prophecy foreseeing their civilization's downfall. The Almighty realizes that Evolet is merely the herald of the true hunter. D'Leh starts a rebellion among the slaves, killing many of the Almighty's forces, though Ka'Ren is killed.
The Almighty offers Evolet and the other hunters to D'Leh in exchange for abandoning his rebellion. D'Leh feigns acceptance but kills the Almighty with a spear. During the ensuing battle, Evolet is killed by the warlord who is then killed by D'Leh, but is restored to life when Old Mother sacrifices herself. With the Almighty dead and his civilization destroyed, the Yagahl bid farewell to the other tribes and return home with seeds given to them by the Naku to start a new life.
Steven Strait as D'Leh, a mammoth hunter.
Camilla Belle as Evolet, D'Leh's wife and the only survivor of a tribe which was killed off by the "four-legged demons" (fierce warriors on horseback); she was spared because of her blue eyes, which marked her as unique.
Cliff Curtis as Tic'Tic, D'Leh's mentor and friend.[4]
Joel Virgel as Nakudu, leader of the Naku tribe.
Affif Ben Badra as Warlord, the leader of the "Four Legged Demons".
Mo Zinal as Ka'Ren.
Nathanael Baring as Baku.
Marco Khan as One-Eye, Warlord's main henchman.
Mona Hammond as Old Mother, the Yagahl wise old woman.
Joel Fry as Lu'Kibu
Reece Ritchie as Moha.
Piers Stubbs as Young Moha.
Junior Oliphant as Tudu, Nakudu's son.
Kristian Beazley as D'Leh's father, who had lived with the Naku tribe and learned agriculture from them.
Boubacar Badaine as Quina, leader of another tribe.
Farouk Valley-Omar as the High Priest.
Tim Barlow as The Almighty, a tall, blue-eyed man who dresses in long white robes and a face-concealing veil. He is the last of three kings and the last of the Atlanteans.
Omar Sharif as Narrator.