In 1821, a British sailing ship, the Becket, anchors off the New Zealand coast. Philip Wayne and Paddy Clarke, respectively First Mate and Bos'un, land to explore. They discover a Māori burial cave, but are captured by the local tribe. Accused of sacrilege, they manage to impress the tribesmen enough to be offered a trial by challenge, in which Wayne succeeds. The Māori chief, Hongi Tepe, is impressed enough to adopt Wayne and allot him a portion of land. The sailors return to the ship which sails back to England.
Arriving there, Wayne and Clarke are set up by the corrupt Captain Bryce on charges of murdering the natives and bringing Britain into disrepute because they have a severed Māori head in their trunk. This had been presented to Wayne as a traditional gift by the Māori chief, but, rejected by him, Bryce had recovered it. Found guilty, Wayne and Clarke have to pay heavy fines to avoid imprisonment. Wayne decides to leave Britain to find a new life and to return to New Zealand. Nevertheless, his fiancée, Marion Southey, still wants to marry him. They sail over, with Clarke, on a private ship and Wayne builds a house close to the Māori tribe he had met before.
The house is completed and a tenuous peace is established with the local Māori, although some remain hostile. Marion starts teaching Hongi Tepe and some others English, using the Bible, and tells them about her Christian religion. The chief's wife Moana hovers around Wayne frequently.
The Becket returns and Wayne confronts Bryce, who is found to be smuggling severed heads of dead Māori captives into Britain as potentially profitable 'souvenirs'. News later arrives by the six-monthly ship that Wayne has been appointed a justice of the peace for his locality, and also that he and Clarke have been exonerated by a court of appeal.
Wishart and Sergeant Paul join the small group just as Marion finds herself pregnant. After the birth, Moana follows Wayne when he goes hunting, and as he settles down to sleep she joins him and they kiss. Hongi Tepe sees them and wants to kill Moana, as is the tribal custom, but his new-found Christianity sways him to let her live. However, a rift between the English and Māori begins.
Wishart accidentally shoots a Māori's dog (thinking it is a goat) and the owner starts fighting him. His gun goes off and shoots the warrior dead. The Māori capture Wishart. Wayne is determined to dispense justice, telling the Māori that he is acting with the authority of his own powerful king. The chief's loyalties are also torn as he knows about Wayne's treachery. Wayne gets Wishart away by promising the Māori that he will be returned to England for trial by his own people. However, they then fear a reprisal attack by the Māori.
Wayne tells Marion that he has been "unfaithful" and although deeply hurt she says she still loves him. Meanwhile, Hongi Tepe's tribe has formed a truce with their local enemy, and the enemy tribe declare a desire to kill the colonists. Moana hears this and goes to warn Wayne, but she is waylaid by the hostile Māori.
A battle begins in the night, and the colonists defend themselves. Initially successful because of their muskets, the colonists eventually find themselves outnumbered and under siege. The attackers use large catapults and fire-bombs to set the house alight. Hongi Tepe's tribe appear and start fighting their old enemies. In mid-battle, Wayne saves Hongi Tepe's life by shooting his attacker. As the battle appears won, Wishart is killed by a spear, and then, with the house ablaze, the roof collapses, killing all the colonists.
The sole British survivor is Marion's young baby, Richard, whom Marion had secreted in a safe place outside, and who is found and adopted by Hongi Tepe. Finally, the friendly Māori watch a new group of colonists arriving on the beach.
Wayne and his companions confront escalating tensions with the Māori after a fatal shooting, navigate accusations and personal betrayals, and ultimately broker a fragile peace as Wayne is exonerated and reconciles with Marion.
The ending reflects the film's ongoing negotiation between colonial authority and indigenous sovereignty, as personal and cultural conflicts come to a head. Wayne's journey culminates in hard-won acceptance and a tentative harmony with the Māori, while his relationship with Marion survives personal strife. The film lands on the uneasy reality of coexistence rather than a neatly resolved frontier fantasy.
