Centurionis a 2010 British action thriller film directed by Neil Marshall , loosely based on the massacre of the Ninth Legion in Caledonia in the second century AD. The film stars Michael Fassbender , Olga Kurylenko and Dominic West .

It is AD 117 and the Roman garrisons are struggling to contain the Picts , the original inhabitants of the Scottish Highlands . The Picts, under their king, Gorlacon, are perfecting guerrilla warfare and are eliminating Roman outposts one by one. Centurion Quintus Dias is the only survivor of a Pictish raid and is taken prisoner by Vortix. In the meantime, Agricola, the Roman governor of Britannia wants to obtain favour with the central administration, hoping to secure a transfer back to the comforts of Rome. He dispatches the Ninth Legion to the front under General Titus Flavius Virilus, with orders to eradicate the Pict threat, providing him with a Brigantian scout, a mute woman, Etain.

As the legion marches north, they encounter Dias, who has escaped but has been pursued by three of Gorlacon's men. After killing the Picts and saving Dias, Virilus learns of Dias's encounter with Gorlacon, as well as his escape from the Picts' settlement, and he proudly makes Quintus one of his centurions. The general soon realizes that Quintus's father was a famous gladiator, who won a fight that earned him his freedom. Dias soon meets and befriends two Roman officers in the legion, a veteran named Bothos and a young Roman soldier named Thax.

Etain, who hates the Romans for murdering her family, betrays the legion to Gorlacon; the Romans walk into a trap and are annihilated, while the general is captured by Pictish warriors. Dias, Bothos, and Thax, along with four other survivors, a veteran named "Brick", two Greco-Roman legionaries named Macros and Leonidas, and Tarak, a cook from the Hindu Kush , learn that Virilus has been taken prisoner and set out to rescue him. After a few days' travel, they find the Pict settlement and sneak in at nightfall. They silently kill several sentries, but fail to break the general's chains; he orders them to leave him and get back to the safety of Roman territory. As they retreat, Thax kills Gorlacon's young son and recovers General Virilus's helmet. The next morning, after the dead boy is cremated, the general is given a sword and made to duel with Etain, who kills him.

The seven decide to return south via a long detour over the mountains, while Etain, Aeron, Vortix, and a detachment of seven Pictish warriors are sent to kill them, in revenge for the king's son. After several days' pursuit, they eventually catch up with the fugitives, who jump off a cliff into a river. Tarak is killed by Aeron and another Pict archer before he can jump; the others survive the fall, but Macros and Thax end up separated from the others, discover Tarak's body floating down the river, and are pursued by a pack of wolves.

With night falling, Dias and his group camp for the night, only to realize that their trackers have set up camp nearby. Dias and Brick launch a night raid on the enemy camp, killing two men and severely wounding a third, but do not find Etain. Interrogating the wounded Pict, Quintus learns of the death of Gorlacon's son, and that the king has sworn vengeance on their heads. He also learns that Etain has launched her own attack on the Roman camp. He and Brick finish off the Pict and return to their camp, only to discover that Leonidas was killed and Bothos injured.

Macros and Thax, meanwhile, are still running from the wolves, with Macros, the faster runner, staying well clear of Thax. As the two Romans run across an open field with the wolves in close pursuit, Thax eventually falls and cries out to his comrade for help. When Macros returns to help him, Thax slices through Macros' hamstrings to prevent him from running, allowing Thax to escape while the wolves attack and devour his former comrade.

Dias, Bothos and Brick happen upon a hut in the forest and befriend Arianne, a Pict exile accused of witchcraft, who lives there. She shelters them, provides food and medical attention, and tells Dias that Etain has been born to fill her empty soul with Roman blood. When Etain comes the following day, Arianne confronts her while the Romans hide under the floorboards, forcing Etain to leave infuriated. The next morning, with Bothos well enough to travel, they leave Arianne, who, having developed something of a connection with Dias, provides them with additional food, to travel to a nearby garrison.

On arrival, they find it abandoned: an order on a wall informs them that Roman troops have retreated south, to set up a new defensive line, by the orders of Emperor Hadrian . As they see Etain and her group of Picts approach, they set up a defensive position inside the fort. Bothos kills Vortix and a female Pict warrior, Dias kills Etain and two Picts, and Brick kills Aeron and the last Pict warrior. However, before the Picts are defeated, Brick is killed by a spear thrown from Etain.

Camping overnight on their way south, Dias and Bothos are reunited with Thax and the trio continue onwards. Upon reaching Hadrian's Wall , Thax threatens Dias, who says that he will report his crimes and the two fight, with Dias as the victor. Bothos, riding joyfully towards the Roman construction works, is mistaken for a Pict and shot by Roman archers. When Dias enters the camp he reports the situation to the governor. Agricola, concerned that, should news of the Legion's annihilation become common knowledge, other tribes may rise up against them, and also not wishing his record to be tainted by a military failure, decides that it would be better if the Ninth Legion's fate remained a mystery and thus Dias must be killed.

The governor's daughter is trusted with Dias's assassination. He manages to disrupt the attempt on his life, killing two legionaries in the process, though he is grievously wounded in the thigh during the fracas. Dias confronts Agricola's daughter and soon learns that they want to bury the truth about General Virilus' and the Ninth Legion's fate, along with him. She says to him that he is too much of a risk. He escapes the camp and returns to Arianne in the forest. As he lies weakened from blood loss in her arms by the stream, he and Arianne embrace each other with a kiss. The film ends as Quintus Dias repeats the film's opening line "...this is neither the beginning nor the end of my story."