The Exorcist (1973) is the sensational, shocking horror story about devil possession and the subsequent exorcism of the demonic spirits from a young, innocent girl (of a divorced family). The Exorcist was notable for being one of the biggest box-office successes (and one of the first 'blockbusters' in film history, predating Jaws (1975)), and surpassing The Godfather (1972) as the biggest money-maker of its time. And it remains one of the few horror films nominated for Best Picture. However, it was also one of the most opposed films for its controversial content. Roman Polanski's successful Rosemary's Baby (1968) played upon similar fears of devil possession. Originally X-rated, the film was released as an uncut 'R' rating which allowed minors to view the film if accompanied by an adult.

The film's screenplay - a horror-tinged western (and tale of good vs. evil), was faithfully based upon author William Peter Blatty's 1971 best-selling theological-horror novel of the same name. Academy-Award winning director William Friedkin (previously known for The French Connection (1971)) created a frightening, horror film masterpiece, with sensational, nauseating, horrendous special effects (360 degree head-rotation, self-mutilation/masturbation with a crucifix, the projectile spewing of green puke, a mixture of split-pea soup and oatmeal, etc.). The film also featured the terrific acting debut of 12-year old actress Linda Blair, who played the helpless girl possessed by demons. The recognizable opening instrumental tune, titled Tubular Bells (by Mike Oldfield), eventually became a #1 single on the Billboard charts - and the first big seller for Virgin Records. The film's poster described:

Something almost beyond comprehension is happening to a girl on this street, in this house and a man has been sent for as a last resort. This man is The Exorcist.

The controversial nature of the film's content - exorcism (accompanied by blasphemies, obscenities and graphic physical shocks), was supposedly based upon an authentic, nearly two-month long exorcism performed in 1949 on a 14-year old boy (with pseudonym "Robbie Mannheim") in Mt. Rainier, Maryland by the Catholic Church (in the form of a fifty-two year old Jesuit priest named Fr. William S. Bowdern and Fr. Raymond Bishop). The official exorcism was reported in Thomas B. Allen's and Carl Brandt's 1993 book Possessed: The True Story of an Exorcism. [Possessed (2000) was also a pay-TV-cable Showtime movie of the same name, starring Timothy Dalton.] The film's plot was also partially inspired by a similar demonic possession case in Earling, Iowa in 1928.

The film was enormously popular with moviegoers at Christmas-time of 1973, but some portions of the viewing audience fled from theaters due to nausea or sheer fright/anger, especially during the long sequence of invasive medical testing performed on the hapless patient. Its tale of the devil came at a difficult and disordered time when the world had just experienced the end of the Vietnam War (US troop withdrawal and the fall of Saigon) and at the time of the coverup of the Watergate office break-in (also in Washington, D.C.). Friction developed between director Friedkin and various cast and crew members during production, and there were additional post-production conflicts between Friedkin and Blatty. Other disturbing events that affected some of the film's stars (injury and death) also plagued the production.

Critically, it was presented with ten Academy Award nominations, two of which won (Best Adapted Screenplay and Best Sound). The other eight nominations included: Best Picture, Best Actress (Ellen Burstyn), Best Supporting Actor (Jason Miller), Best Supporting Actress (Linda Blair), Best Director, Best Cinematography (Owen Roizman), Best Art Direction/Set Decoration, and Best Film Editing. [Until The Silence of the Lambs (1991), the film was the only horror film to be nominated for Best Picture in Academy Award history.]

Unfortunately, the film spawned imitations (i.e., The Omen trilogy, the Italian knockoff films Beyond the Door (1974) and The Tempter (1974) (aka The Anti-Christ), the 'blaxploitation' clone Abby (1974), and the UK's The Devil Within Her (1975)), a spoof-parody of all the 'Exorcist' films (Repossessed (1990) with Linda Blair again possessed while watching the TV show of evangelists Ernest and Fanny Rae Weller (Ned Beatty and Linda Schwab) and with Leslie Nielsen as an ex-exorcist named Father Jedediah Mayii), and the biased "true story" courtroom drama The Exorcism of Emily Rose (2005).

It also inspired many inferior sequels of its own:

After a few blood-red credits on a black background, the film opens with a prologue. The locale is an archaeological dig site deep in the arid desert of Northern Iraq - near the ancient town of Nineveh. An Arabic prayer is chanted on the soundtrack behind an image of an oblong, burnt-reddish sun. Workers dig inexorably with pick-axes through mounds of dirt to uncover ancient artifacts. A young boy in a red head-dress runs through the weaving, maze-like trenches to summon one of the supervisors. The camera shoots through his legs as he speaks in Arabic: "(Subtitle): They found something...small pieces...At the base of the mound."

Father Lankester Merrin (Max von Sydow), an elderly, scholarly Jesuit Catholic priest and archaeologist, is told that ancient objects have been unearthed during his search for evil: "Lamps, arrowheads, coins..." Merrin inspects a small silver, Christian medallion (depicting Mary and the baby Jesus) and observes that it is unusual to find it buried in a pre-Christian location: "This is strange...Not of the same period." Merrin then digs in a crevice near the Christian objects and discovers a small, greenish, gargoyle-like stone amulet or statuette [in the figure of the Mesopotamian demon Pazuzu, known for its serpent-like phallus]. [The Iraqi sequence sets a tone of foreboding and establishes the presence of 'Good' and 'Evil' - it also foreshadows the battle between the two forces later in the film.]

In the Iraqi marketplace on the streets of Mosul, with a throbbing, drumming sound, the strain is evident as Merrin's hand shakes when he takes his heart medicine. Iron workers clang their hammers on anvils near a red-hot burning furnace. One of the steelworkers turns toward Merrin, revealing his blind right eye [an allusion to future horrors in the film]. Back in the curator's office, as Merrin eyes the ancient Pazuzu amulet, he is told: "Evil against evil." Ominously, the swinging pendulum of the clock behind him stops working. The curator knows Merrin will be leaving to go home to the States: "I wish you didn't have to go." Weary and exhausted, Merrin replies: "There is something I must do." He passes by prostrate Muslim worshippers and into a dark passageway. When he emerges in the narrow, sunlit street, he is nearly run down by a fast-moving, horse-drawn carriage carrying an old woman in a black droshky, worn over her face like a shroud.

After driving his jeep to an ancient temple ruins guarded by armed, white and black-garbed watchmen, he walks up to a full-sized stone statue of the demon Pazuzu. Nearby, two dogs begin fighting and snarling at each other in the dust. [This struggle foreshadows the eventual conflict between good (the priest) and evil (the possessed girl), and also hints at the theme of "evil against evil" - Karras' deliberate 'evil' act of demon possession to save Regan.] He again has a premonition that the amulet is a concrete manifestation that something evil has been unearthed - the soundtrack simulates an eerie, shrieking chord, symbolizing the loosing of ancient, pagan evil in the world. The camera zooms in on the face of the open-mouthed, fearsome creature. As he confronts the demonic statue that has been called up for protection by the amulet's discovery, the wind blows dust over the scene as he feels all around him the presence of the devil.

In a clever transitional dissolve linking two distant locales and their coincidental association, the scene from the desert (a sizzling view of the orb of the dawning sun) dissolves into the sounds and views of early morning traffic crossing the Potomac in Georgetown outside Washington, D.C. The camera zooms into one of the Georgetown houses where a hand turns on a different kind of bright light - a white electric lamp. Inside her bedroom, divorced mother and actress Chris MacNeil (Ellen Burstyn, reportedly modeling her role on actress Shirley MacLaine) is working on lines in her latest script. She hears unsettling sounds from the attic similar to the dirt-digging sounds of the prologue. [This form of infestation is the first classic stage of possession.] She investigates - following the sounds to her 12-year old daughter Regan's (Linda Blair) bedroom where the young girl is sleeping. The covers are pulled back and the window is inexplicably wide open with fluttering curtains - she senses a certain coldness or presence in the room. Downstairs in the kitchen, Chris instructs housekeeper Karl (Rudolf Schundler) to purchase traps for "rats in the attic."

The next minimalist scene introduces other film characters and a 'film within a film.' On the Georgetown University campus, Chris emerges from a movie-set trailer on the set of Warner Bros. Inc.' Crash Course (now filming at locations in California and Washington, D.C.). (Later, Chris expresses how she despises the film when she describes the movie as "kinda like the, uh, Walt Disney version of the Ho Chi Minh story...") [William Peter Blatty makes a brief cameo appearance as an upset producer, telling the director: "Is the scene really essential? Would you just consider it, whether or not..."] The scene that is being filmed at the Catholic school dramatizes early 1970s student protest that threatens to tear down the historic stone walls of the university. Chris, a representative of the academic-adult population, questions the British director Burke Dennings (Jack MacGowran, who died one week after completing his scenes in the film) about the unrealistic plot of adolescent counter-cultural turmoil. One of the curious onlookers among a crowd of students, a Jesuit priest (in black) from the university, named Father Damien Karras (Jason Miller in his debut screen role), smiles amusedly after overhearing their conversation.

A few moments later into the shoot, when Chris grabs a bullhorn and tells the rebellious students in the crowd: "If you want to effect any change, you have to do it within the system," a long crane shot finds Father Karras walking away from the crowd and the filming - he turns back to watch for a moment, and then continues his departure in serious thought. [To accentuate one of the film's themes, the actor's lines are deliberately juxtaposed with the priest's departure, since he is experiencing an inner struggle of religious faith within his own system - the church.]

After the day's shoot is finished, Chris walks the leaf-covered street from the campus to her home, accompanied by the tinkling, mesmerizing sounds of "Tubular Bells' (by Mike Oldfield). It is Halloween, and children run by in their masks and costumes. [Historically, scary Halloween masks, pumpkin faces, and costumes were designed to ward off evil spirits - another manifestation of the film's theme.] For a brief moment, a roaring black motorbike that passes behind her slightly drowns out the sounds of the bells. Two nuns trailing billowing black and white habits walk down a road in front of a brick wall. Now in her neighborhood, she turns and hears, from a distance, the priest Karras counseling a fellow priest (until his spiritual words are overshadowed by the loud, mechanical roar of an overhead jet engine):

There's not a day in my life that I don't feel like a fraud. Other priests, doctors, lawyers - I talk to them all. I don't know anyone who hasn't felt that.

As priest Karras rises up from an underground stairwell, emerging into the noisy track area of the New York City subway where the tracks spew jets of steam, the camera pans past a soft-drink vending machine, emblazoned with: "TRAVEL REFRESHED." On the dirty, trash-littered platform of the subway station, he turns to hear a tattered, derelict drunk begging with an outstretched hand:

Father, could you help an old altar boy. I'm Cat'lick.

Wrapped up in his own problems and unable to be charitable in this subway encounter, Father Karras turns away from the wretched man whose bearded, sweaty face is momentarily illuminated in flashes by the window lights of a passing subway.

He visits his dying, sick mother, Mother Karras (Vasiliki Maliaros) who lives in humble, pauper's conditions by herself (after he left her and moved to the priesthood in Georgetown) in a derelict area of New York City. The street, lined with run-down housing, is populated with unruly kids, drunks, graffiti, and litter. After first stopping in his own room and reflecting on his past [two photographs of his early boxing career, trophies, a childhood photograph, and a picture of a former girlfriend], he enters his Mama's room. As he carefully binds his mother's injured leg and then lights a cigarette for a smoke [atypical for a priest], he suggests moving her elsewhere, but she is a stoic, stubborn, Greek immigrant woman from the Old World, and she doesn't want to move:

Damien: Mama, I could take you somewhere where you'd be safe. You wouldn't be alone. There would be people around. You know, you wouldn't be sitting here listening to a radio.
Mother: (She first speaks in her native tongue) ...You understand me? This is my house and I'm not going no place. Dimmy, you're worried for something?
Damien: No, Mama.
Mother: You're not happy. Tell me, what is the matter?
Damien: Mama, I'm all right, I'm fine, really I am.