Gathered together by young Hubert (Tom Rhys Harries), a small band of hired swords gather inside his families castle intent on holding off evil Celtic Tribesmen hell-bent on revenge for the death of their leaders' son: a young mercenary named Guy (Tom Austen) whose soul is wracked with guilt over the atrocities he has committed during the days and years after the great battle of Rochester Castle and his burgeoning feelings for Kate, his cousin (Roxanne McKee), ; battle-hardened mercenaries such as Berenger (David Caves), who fight not for God and country for money and bloodlust.

When the Vatican observatory priest sees the appearance of a comet, the Church is sure that it confirms the eve of the Armageddon. Meanwhile, the USA President's godson Robert Thorn is informed in the maternity in Rome by Father Spiletto that his wife Katherine has just lost her baby and she had troubles with her uterus and would not have another pregnancy. Spiletto suggests Robert that another just born child that lost his mother could be the substituted for his son, and Robert accepts the child and gives the name of Damien. Robert is promoted to ambassador in London after a tragic accident. When Damien's nanny commits suicide in his birthday party, a substitute, Mrs. Baylock, comes to work and live with the family. Along the years, Katherine realizes that Damien is evil, while Robert is contacted by Father Brennan, who tells him that Damien is the son of devil. When the priest dies in a bizarre accident...