Robert Thorn, an American diplomat stationed in Italy, is told that his son was stillborn. Unknown to his unconscious wife, Katherine, Robert adopts an orphaned newborn at the suggestion of the hospital's chaplain
Catholic priest, Father Spiletto. Naming him
Damien, Robert and Katherine raise the boy. Robert's career ascends over the next 5 years. He is named Deputy Ambassador to the
Court of St. James's in the United Kingdom. Following the death of the previous ambassador in a suspicious vehicle fire caused by a vagrant, Robert assumes his position and settles in a large estate just outside London. However, disturbing events begin to occur, including the suicide of Damien's nanny, who saw a black dog and made eye contact with it, at his birthday party. Robert is approached by Father Brennan, who claims to have been involved with events surrounding Damien's birth. Meanwhile, photographer Keith Jennings finds that several of his photographs contain mysterious omens, including premonitions of people's deaths. A new nanny, Mrs. Baylock, is hired. Tension rises when Mrs. Baylock starts to make decisions without the consent of the Thorns, including adopting a
Rottweiler for Damien's protection. Following an incident near a chapel in which Damien attacks Katherine, she begins experiencing vivid dreams about her son, one of these involving a red-hooded
jackal skeleton. When the Thorns visit a zoo, the animals react violently at the sight of Damien. Katherine begins to wonder if there is something wrong with Damien. Father Brennan confronts Robert, telling him that Damien's mother was a jackal and that the boy is the
Antichrist. He explains that Damien must die, and a man named Bugenhagen, located in
Megiddo, can help. After being rebuked, Father Brennan is killed during a lightning storm. Katherine discovers she is pregnant and is determined to get an abortion, in fear of having a child similar to Damien. Soon afterward, Damien causes an accident in which Katherine is severely injured, resulting in her miscarriage. While in the hospital, Katherine confides in Robert that she has suspicions that Damien is evil. Jennings meets with Robert and shows him the photographs, including a new omen of his death. Robert decides to rendezvous with Jennings and search for Damien's biological mother. The pair discovers the hospital where Damien was delivered has since been demolished after a fire. They travel to Subiaco and meet a deformed Father Spiletto, who directs them to a graveyard. There, they find the grave of Damien's mother, who is revealed to have indeed been a jackal. In the neighboring tomb, Robert discovers the corpse of his murdered biological son. He and Jennings are attacked by a pack of dogs and barely escape. Mrs. Baylock visits Katherine in the hospital and causes her to have an
air embolism, which kills her. Learning of Katherine's death, Robert goes to Megiddo, meets Bugenhagen, and receives instructions on how to kill Damien on consecrated ground with 7 sacrificial daggers. Bugenhagen tells Robert to examine Damien for a birthmark in the shape of
three sixes ("666"). However, Robert refuses to kill his son and throws the daggers on the ground. While reaching down to pick up the daggers, Jennings is suddenly decapitated by a falling sign. Robert takes the daggers, arrives home, and is attacked by Mrs. Baylock's Rottweiler, which he traps in the basement. In Damien's room, he finds the 666 birthmark. Mrs. Baylock attacks Robert. He fends her off, takes Damien, and drives to a nearby cathedral, running over Mrs. Baylock in the process. Pursued by the police, Robert flees to a church to kill Damien but is shot dead before he can by a
Diplomatic Protection officer. As the Pope simultaneously dies, Robert's funeral is attended by the President of the United States, who holds Damien's hand. Damien then looks at the audience and glances regretfully. == Cast ==