At Temptations Limited, an antique and curio shop, Edward Charlton offers the Proprietor £25 for a mirror worth £250, telling the old man that it is a reproduction. That night, Edward shows off his find to his girl friend, Pamela, and two other couples, congratulating himself for cheating the Proprietor. The mirror’s exotic look prompts one woman to suggest a séance. The group assembles at the table, gazing at a candle. When Edward tells everyone to concentrate, the flame becomes a blue flare that sparks up each time he speaks. The mirror becomes cloudy and the face of a bearded man appears. Edward suddenly finds himself in a bleak nightscape, where the stranger stabs him and, just as suddenly is back among his friends. Later that night, Edward awakens as the Face appears, telling him, "You must feed me!" Later, Edward brings home a prostitute and, at the Face’s signal, Edward stabs her. He wakes up in bed with blood on his pajamas and blood on the sofa, and finds a bloody knife in the kitchen. Again, as Edward wakes to find his clothes and sheets stained with blood, the Face demands to be fed. Edward asks desperately, "How many more?" It replies, "Until I am fulfilled." After another murder, Edward asks the Face why he must kill. It explains that, as it gave sacrifices, so must Edward, enabling the Face to "walk in daylight." Edward smashes the mirror, but it quickly restores itself. When Pamela calls, the Face coerces Edward to invite her over. However, when she arrives, Edward convinces the Face that her disappearance would create suspicion. Edward sends Pamela away and the Face demands another victim. Downstairs, a drop of blood falls from the ceiling of Mr. Jeffries’s apartment, and he complains to Edward about the constant noise, including the late-night hammering, and the stains on his ceiling. Edward closes the door and quickly finds a body under the floorboards, then opens the door to Jeffries and kills him. Soon after, Edward sees the Face as a fully restored man. The Face will now join the others of his kind, who are "beyond the ultimate." Inviting Edward to experience "the ultimate," the Face holds the knife as Edward thrusts himself onto it. Other tenants rent the apartment after Edward’s death, but the mirror remains. One of them is a young man who holds a séance with his friends. Now, Edward’s face appears in the mirror. Back at Temptations Limited, Christopher Lowe gazes at the Distinguished Service Order medal in the store window. Nearby, Jim Underwood, a peddler wearing several military medals, sells Christopher some shoelaces. At home, Christopher’s wife Mabel tears the laces apart with little effort, and mocks his gullibility, as their son, Stephen, snickers. At dinner, Christopher finds the meal disappointing, eliciting a tirade from Mabel about his inadequacy as a provider. Returning to the peddler, lies about being a decorated hero, prompting a salute from Jim. At Temptations Limited, Christopher is unable to buy the medal without certification, so he steals it when the Proprietor’s back is turned. Christopher shows the medal to Jim, who invites him to tea. At home, Mabel mentions that someone had taken her picture that day for no apparent reason, but Christopher is indifferent. That Thursday at tea, Jim and his daughter Emily both treat Christopher with respect and admiration. The next day, while on a bus with Stephen, an unseen stranger removes a lock of Mabel’s hair. At the Underwood flat, Emily enthusiastically accepts a watch from Christopher, who admits that his marriage is a failure. That night, Mabel dreams of a ghastly woman stabbing her in the neck. On his next visit, Christopher is left alone with Emily, who offers to do anything he demands. They sleep together and, in the morning, Christopher finds Emily lighting a black candle in the living room. When she offers to stab a voodoo doll of Mabel, he humors her, assuming it to be harmless, but later returns home to find Mabel dead and Stephen in tears. Jim and Emily appear at the door and link arms as "The Wedding March" plays. Christopher, Stephen, Jim and Emily surround a wedding cake decorated with a small bride-and-groom. When Christopher asks Emily to cut the cake, she starts with the head of the plastic groom. Christopher falls dead as blood pours from his scalp. The Underwoods assure Stephen that they always answer children’s prayers, "one way or another." At Temptations Limited again, Reggie Warren examines snuffboxes, unobserved by the Proprietor. He switches tags on two boxes, pricing a £40 box at £5. When the Proprietor appears, Reggie pays him £4. While reading his newspaper on the commuter train, Reggie is interrupted by Madame Orloff, a psychic who sees an "elemental" in his left shoulder. He ignores her, but she persists, explaining that an elemental is a spirit of air, fire and water that "sucks the very juices of the soul," and this one is homicidal. She hands Reggie her card as he disembarks. At home, Reggie’s dog growls at him. His wife Susan then accuses him of striking her arm, in spite of his denials. That night in bed, Susan feels her hand being held tightly, then feels herself being strangled. She blames Reggie, even though his hands are nowhere near her. She also detects a horrible stench and runs gagging to the bathroom. Reggie phones Orloff, who agrees to be there the next morning. She also tells him that he must fast until then, or the creature may take over his body. Upon her arrival, Orloff sees that the elemental has grown. The room is darkened and Orloff begins her incantation. The house trembles and, after a short interval, Orloff needs a break. She also informs Reggie that Susan attracts elementals "like flies to a dung heap." When the exorcism resumes, the tremors are accompanied by explosions and, with the shattering of a window, the job is complete. Reggie happily pays Orloff’s £50 fee. Later, as the Warrens enjoy cocktails, a strange sound emanates from the ceiling. Reggie climbs the stairs to investigate and immediately tumbles back down. Susan stands over him with a fireplace poker, announcing in an otherworldly voice, "You denied me life," before crushing his skull. Susan, possessed by the elemental, crashes through a wall to the outside, shouting, "Life, life, life!" At Temptations Limited, the Proprietor tells William Seaton about an elaborately carved door, explaining that it once opened into a magnificent blue room. The price is £50, but William only has £40. The Proprietor goes to the back room for a receipt as William stares at his money on the counter. Later, the Proprietor counts the money, one pound at a time. At the Seaton home, the door is attached to a stationery cupboard. William removes some dust, which looks like dried blood. Rosemary, his wife, is able to envision the blue room as it looked in the 17th century. Later, William opens the door to find the blue room covered in dust and cobwebs. As he opens a large book, he hears approaching footsteps and runs from the room. When he opens the door again, the room is gone. Later, when the door opens on its own, William returns to the book, An Experiment in Darkness, by Sir Michael Sinclair. It reveals that the door was soaked in warm blood, and that the room is sustained by those who have been sacrificed to it, especially women who "hath a more enduring quality." Sinclair enters, chasing William through the door. When William tells Rosemary of his experience, the room has disappeared. Believing that Sinclair is after Rosemary, the Seatons try to escape, but they are locked inside. Sinclair reappears and carries Rosemary inside the room while beckoning William to join them. William grabs an axe and attacks the door, which bleeds from every cut. Sinclair fights back as the room crumbles, but when William removes the door from its hinges, Sinclair is reduced to dust and the room vanishes. At the antique shop, the Proprietor counts out the last of William’s £40. A burglar quietly enters the shop as the Proprietor loads a pair of flintlock pistols. He hands them to the burglar, who attempts to rob the store. As the Proprietor approaches unfazed, the burglar fires, then throws the guns. The burglar is startled by a skeleton, and he falls into a box lined with metal spikes. As the shop door opens, the Proprietor beckons an unseen customer. The text on the door reads, "OFFERS YOU CANNOT RESIST."