- This page is about the film. For other pages, see the disambiguation page.
Mike Enslin is a skeptic and author who debunks supernatural occurrences after the untimely death of his daughter Katie. After his latest book, he receives an anonymous postcard of the Dolphin Hotel in New York City bearing the message "don't enter 1408". Viewing this as a challenge, Enslin attempts to book a reservation for room 1408, but the hotel will not rent him the room. However, after being informed by Enslin's agent, Sam Farrell, that the Fair Housing Act requires hotels to rent unoccupied rooms, the Dolphin reluctantly reserves room 1408 for Enslin.
Arriving at the Dolphin, Enslin is pulled aside by the hotel's manager, Gerald Olin, who warns him that no one has lasted more than an hour in 1408. Olin offers Enslin an upgrade to the penthouse suite, access to documents regarding the deaths in 1408, and an $800 bottle of cognac if Enslin would abandon his plan to stay at 1408. Enslin accepts the documents and the cognac but insists on staying in the room, frustrating Olin. The manager gives him the key, warning him that "it's an evil fucking room".
Once inside the room, Enslin pulls out his Mini Cassette recorder and dictates on the unremarkability of room 1408. As he examines the room, the radio suddenly starts blaring "We've Only Just Begun" by The Carpenters, initially thinking it is just a gag cooked up by Olin. Later, Enslin is startled again as the clock radio begins to play the same song. When he turns the clock off the display flickers and changes to read "60:00", then starts counting down from 60 minutes. Suddenly, Enslin is unable to hear anything, apart from a tinnitus-like ringing in his ears, and opens the window to check his hearing; the window slams down, cutting a large gash in the top of his hand. He rushes to the bathroom to wash the wound in the sink, but the water suddenly becomes boiling hot and damages his wound even further. His hearing quickly returns and he bandages his hand using a bandana from his bag. Wishing to go to a hospital, Enslin attempts to leave the room; however his key breaks off in the door. He still manages to unlock the door, but then the doorknob falls off, trapping him inside 1408.
Enslin begins to see and hear things, including visions of his daughter's time in the hospital shortly before her death, but he initially dismisses them as hallucinations. Among one of these strange visions is a face-to-face encounter with his own father, who tells him, "As I was, you are. As I am, you will be", a quote attributed to the Roman poet Horace regarding death. He makes several attempts to free himself from the room such as crawling through the air vents, where he is seen being chased by a ghost (one of 1408's earlier victims), or trying to crawl outside on the ledge to the next room, but all end in failure. He manages to contact his estranged wife Lily via video chat, but the conversation ends abruptly when the sprinkler system shorts out his laptop. All the while the room temperature drops, eventually to subzero temperatures. However, his laptop starts working again and he hears Lily calling out to him via video chat, but a doppelgänger of him hijacks the conversation, urging Lily to come the hotel immediately and enter room 1408. As a panicked Enslin watches this conversation end, the doppelgänger looks at him directly and winks. The room begins to shake violently and the interior cracks and explodes as water fills the room, pulling Enslin under the surface.
Enslin wakes up on the beach, the result of an earlier surfing accident that is depicted earlier in the film when he became unconscious. He soon finds Lily at his bedside in the hospital near his home in Los Angeles. She tells him that he was hospitalized after sustaining a concussion. He immediately writes a novel on his experience in 1408 and goes to mail it. This reprieve is short-lived, however, when at the post office a construction crew made up of hotel staff and guests begin to destroy the interior, revealing the walls and floor of 1408 underneath, now fire gutted, and finding himself still trapped in the room. There is a small inscription on the wall visible from the window, reading Burn Me Alive. Enslin then encounters his dead daughter, alive, but dying again, and crumbling to dust as the clock radio's countdown approaches zero; when it finally reaches zero the room changes back to its original, undamaged appearance.
The clock radio resets for another sixty minutes and the phone rings; when Enslin answers, he asks "Why don't you just kill me?" the friendly female voice of the hotel operator informs him that he can relive the hour "again and again" or choose to take advantage of their "express checkout system". A hangman's knot appears in the bedroom and Enslin has a vision of him hanging himself; he tells the operator that he will not be checking out that way. The phone rings again, and the operator reminds him that his wife will be arriving in five minutes and will be sent right up to his room. He responds he is done arguing and is going to end the experience.
Turning the cognac he got earlier from Olin into a Molotov Cocktail, Enslin sets the room on fire, causing the hotel to be evacuated. Lily, who just arrives after she had been summoned by Enslin, is stopped from entering the hotel, but tells the firefighters that Enslin is in 1408. Enslin throws an ashtray through the room's windows, intentionally causing a backdraft to overtake the room just seconds before firefighters batter down the door. They get him out and, though burned, Enslin is told that he will be all right. Enslin attempts to tell the firefighters not to enter the room, as it is "evil". A short while later, a smiling Olin is seen in his office, smoking a cigar and praising Enslin for surviving.
Enslin recovers in a New York hospital, Lily at his bedside. He swears that he saw Katie, but Lily refuses to believe him. After his recovery Enslin moves back in with Lily, beginning work on a new novel about his stay in 1408. While sorting through a box of items from his night in 1408, Enslin comes across his Mini Cassette recorder. After some difficulty he manages to get the tape to play; it begins with Enslin's dictation of 1408's appearance, but cuts in with audio from his interaction with the apparition of his daughter. Lily freezes in shock as she hears her dead daughter's voice coming from the hand-held tape recorder, and the film closes on Enslin meeting her shocked stare with one of grim vindication.