As a series of mysterious events and violent deaths occur around the family and Damien enters childhood, they come to learn he is in fact the prophesied Antichrist.

Released theatrically by 20th Century-Fox in June 1976, The Omen received mixed reviews from critics but was a commercial success, grossing over $60 million at the U.S. box office and becoming one of the highest-grossing films of 1976.

Five years later, Robert is Ambassador to the United Kingdom in London when mysterious phenomena begin to plague the Thorns: a menacing Rottweiler appears at their home, Damien's nanny publicly hangs herself during his fifth birthday party, a new nanny named Mrs. Baylock arrives unexpectedly, Damien violently resists entering a church, and animals at a safari park are terrified by his presence.

Keith shows Robert the photos along with news clippings and Biblical passages from Father Brennan suggesting the coming of the Antichrist.

Robert drags a screaming Damien onto the altar to kill him and begs God to forgive him, but the police arrive on the scene and shoot him as he brandishes the dagger.

[9] Donner favored an ambiguous reading of the script under which it would be left for the audience to decide whether Damien was the Antichrist or whether the series of violent deaths in the film were all just a string of unfortunate accidents.

He turned down the part on July 27, not wanting to spend an entire winter alone in Europe and also concerned that the film might have an exploitative feel if not handled carefully.

These lesser-known facts underscore the tumultuous yet triumphant journey of The Omen, adding to its legacy as a film that transcended its ominous production experiences.

Duren further maintained that the box office success of The Omen, which concerned the first stages of the Apocalypse as the Antichrist is born, reflected the zeitgeist of 1970s America.

Jim Knipfel in The Omen: The Pedigree of a Horror Classic on Den of Geek, opines of The Omen:"[T]here is no single source quite as central and clearly influential as "The Devil's Platform", a 1974 episode from the first season of Kolchak: The Night Stalker, with stars Tom Skerritt (credited as "Tom Skerrit") as Robert Palmer, a young politician whose meteoric rise seemed to come out of nowhere.

Duren wrote that dispensationalism had once been a "fringe" theory within Protestant theology, but due to the popularity of The Omen it is now widely accepted as doctrine.

[29] An original score for the film, including the movie's theme song "Ave Satani", was composed by Jerry Goldsmith, for which he received the only Oscar of his career.

According to Goldsmith's wife, Carol, the composer initially struggled with ideas for the score until one evening when he suddenly, happily announced to her, "I hear voices", referring to an orchestral chorus or choir.

The Omen was released following a successful $2.8 million marketing campaign inspired by the one from Jaws one year prior, with two weeks of sneak previews, a novelization by screenwriter David Seltzer, and the logo with "666" inside the film's title as the centerpiece of the advertisement.

[37] It grossed $4,273,886 in its opening weekend (a then-record for Fox)[37][38] and $60,922,980 in total, ($334,414,696 in 2024,) generating theatrical rentals of $28.5 million in the United States and Canada.

During its release in South Africa under the apartheid regime, the Publication Approval Board cut the final scenes showing the killing of Robert Thorn and Damien's survival.

"[41] Variety praised Richard Donner's direction as "taut" and the performances as "strong", and noted that the script, "sometimes too expository, too predictable, too contrived, is nonetheless a good connective fibre.

[43] Gene Siskel of the Chicago Tribune also awarded 2.5 stars out of 4, lauding the "firepower sound track" and several "memorable" scenes, but finding the story "goofy.

"[44] Kevin Thomas of the Los Angeles Times called it "an absolutely riveting, thoroughly scary experience, a triumph of sleek film craftsmanship that will inevitably but not necessarily unfavorably be compared to The Exorcist.

"[45] Tom Shales of The Washington Post declared, "It's probably the classiest Exorcist copy yet, but as a summer thriller, it can hardly challenge the human appeal and exhilarating impact of last year's Jaws ... Seltzer, busy justifying his baloney premise with Biblical quotations, forgets about narrative logic or empathetic characters.

"[48] Duncan Leigh Cooper of Cineaste wrote, "Despite its improbable story line and abundance of gratuitous violence, The Omen does succeed in its attempt to frighten, terrorize, and just plain scare the pants off most of the audience.

Impressive performances ... plus a chilling mock-religious score by Jerry Goldsmith and the skillful direction of Richard Donner, all contribute to the suspension of disbelief required to draw the audience into the film's web of terror.

"[49] Richard Combs of The Monthly Film Bulletin described the movie as "[a] matter-of-fact exercise in Satanic blood and thunder, both less grandiloquently and less pretentiously put together than The Exorcist ...

In fact, the narrative is so straightforward, and so mundanely concerned with developing ever more ingenious ways, at a rapidly increasing clip, of disposing of its starry cast, that the spiritual torment is skimped.

The site's consensus reads: "The Omen eschews an excess of gore in favor of ramping up the suspense—and creates an enduring, dread-soaked horror classic along the way".

On the other hand, some Protestant groups praised the film, and the California Graduate School of Theology in Glendale presented the filmmakers with a special award during its 1977 commencement ceremonies.

[64] On October 15, 2019, Scream Factory released a deluxe-edition box set—featuring the original film, along with all three sequels and the remake—and featuring newly commissioned bonus materials.

[65] A remake of the same title was released in 2006, starring Liev Schreiber and Julia Stiles in the roles of Robert and Katherine, and Mia Farrow portraying Mrs.

[70] A television series called Damien was in development at the network Lifetime before it was moved to A&E with Bradley James starring in the title role.

The series, acting as a direct sequel to the original film, follows 30-year-old Damien, who has forgotten his demonic past, facing his true identity.