A projectionist in a Detroit theater named Paul (John Leguizamo) is reading about the 16th Century vanishing of the Roanoke Colony, when the lights suddenly go out. He finds that everyone in the theater has vanished, leaving their clothes behind. He runs into a security guard (Arthur Cartwright) holding a flashlight. Paul has a headlamp on, and they guess that people holding lights are protected from whatever lurks in the darkness. The guard goes off to investigate a noise and when his light goes out, he vanishes. Paul hears the guard cry out and his own headlamp goes out. A woman in scrubs, Rosemary (Thandie Newton) is searching for a child named Manny.

The next morning, TV reporter Luke Ryder (Hayden Christensen) wakes up and notices the lights are out. A report from Chicago features a reporter telling people to keep a light on at all times. Three days later, Luke is alone in the darkness, scrounging for flashlight batteries and checking out cars. He finds a tavern powered by a portable generator, where the barmaid’s 12-year-old son James Leary (Jacob Lattimore) is waiting. He insists his mother is in a church down the street and will be back soon. Luke explains to him that it is eleven AM, and the days are getting shorter.

They are joined by Rosemary, still looking for Manny. Paul stumbles in with a concussion. He says he had been taken by the darkness, but his headlamp went back on, and he re-appeared. He recounts the story of Roanoke Colony, where a hundred settlers vanished overnight, and the word CROATOAN was carved into a fencepost. The generator is failing, and Paul needs medical attention. Luke suggests they go to Chicago. He and Rosemary go out to get an abandoned truck. Their flashlights begin losing power and they go into the hospital to find batteries.

Rosemary thinks she hears a baby crying and Luke says it is the dark trying to trick her. She goes to a streetlight and vanishes when it goes out. Back at the bar, the generator is failing and the lights flicker. Paul searches for James in the tunnels under the bar. James is wearing a necklace of glow-sticks and is safe, but Paul vanishes. Luke pushes a truck back to the bar and they use the generator to start the truck. They drive to the nearby church and James gets out to find his mother. Luke drives off, but he returns when he sees the word CROATOAN carved in a sign. The car battery dies, and the lights go out and Luke disappears. James cowers in the church all night, where the candles are going out one by one.

He wakes at daylight and finds that one candle has burned all night. A little girl named Brianna (Taylor Groothius) appears with a solar-powered flashlight. As they leave the church, they see a police horse eating spilled apples and decide to ride it to Chicago. As the sun sets on the two children leaving the city, we see the shadows of Luke, Paul, and Rosemary watching them as darkness falls. The solar light goes on, though James knows that the days are getting shorter, and the light must ultimately fail when the sun goes out entirely.

The film was directed by Brad Anderson, based on a screenplay by Anthony Jaswinski, produced by John Herrick of Herrick Entertainment. Spanish composer Lucas Vidal did the film score, his first. The movie was shown in only six theaters in the US, and was considered a flop, but it made some money in foreign markets, mostly South Korea. It received mixed reviews, though some admired its slow, talky, creepy style. The film was shot in twenty days. Main characters Luke, Paul , (Rose) Mary, and James are named after figures in the Bible. The cast members jogged in place between takes to maintain intensity. The three main characters do not howl in pain when taken by the dark, but say things like, “I exist.” Each one interacts with a secondary character before coming to the bar. And they die or vanish in they order they appear on screen.