NOTE: This spoiler was submitted by Spectre.
The film opens with a voice over by Ramirez (Jacob Vargas) telling us when he was a boy his mother told him about the Devil and how he sometimes liked to personally torture his victims before taking them to hell. He said this act always started with a suicide.
Cut to the building where the story takes place. A man is buffing the floor, oblivious to person who had just jumped out the window and landed on a truck behind him.
Nearby, Detective Bowden (Chris Messina) is talking to his sponsor about forgiveness when he gets the call about the suicide.
Meanwhile five strangers enter the same elevator. They are:
- Ben - A Temp Security guard
- Sarah - Heiress about to see her lawyer
- Vince - A Salesman
- Tony - An ex-soldier
- Jane - An older woman.
The elevator gets stuck, something the security guards Lustiq (Matt Craven) and Ramirez notice. They send Dwight, a handyman, to fix it. The guards can speak to the group, but the group can't talk back. As Dwight is trying to fix things, the lights flicker and Sarah is bitten by something. The group thinks it was Vince that did it and become distrustful of him. Ramirez is becoming frightened as this is starting to remind him of his mother's story. He sees a face in the security feed, but Lustiq tells him to forget it.
Det. Bowden, piecing together that the suicide actually happened at the building with the trapped group, is apprised of the situation. Ramirez talks about the Devil and how it is here with this group, but Bowden counters he doesn't believe in the Devil. Five years ago someone hit his wife's car, killing their son and her. The person only left a note saying, "I'm so sorry". Bowden says there isn't a Devil because people are bad enough without him.
The lights flicker again, and Vince is killed with some broken glass in the neck. The group starts to really panic, and Bowden thinks one of them is a murderer. He calls in the cops, firemen and elevator people to figure out the mess.
Ramirez continues his voiceover, by saying that innocent people are also killed when they try inadvertently to interfere with the Devil's plan.
Dwight, who has to rappel down to the elevator to see if he can fix it, has his harness break and falls until he hits the elevator. The group, who initially believe someone is here to save them, realize within minutes that he is dead.
The lights go out again and Jane winds up hanged by the light's wire. Bowden orders them to a different corner and to not touch each other. Bowden finds out they all have a secret; Ben had hurt people physically, Jane was a thief, Sarah blackmailed men for money, and Vince ran a ponzi scheme. Ramirez tells Bowden more about the Devil myth, how the group each did bad things for this and they cannot be saved. Still trying to find a plausible explanation, Bowden realizes Sarah's husband owns the security company of the building and may have hired Ben to kill her.
The firemen are trying to cut through the wall to get to the elevator so they have Lustiq turn off the gas. However, the Devil thinks he is interfering and causes an accident so he is electrocuted.
The lights begin to flicker again and Ben tells Sarah to stand with him away from Tony. But when they come back on, Ben is killed instead. Tony and Sarah think the other is a killer but are willing to stand down after Bowden talks to them. The lights go out again and Sarah's throat is slashed. Tony is the only one left.
Det. Bowden is approached by Tony's fiancée, telling him he was only there for a job offer. They confirm the sign in sheet and realized he signed in; the only one who didn't was....
The older woman Jane, whose corpse reanimates in front of Tony and the dying Sarah. Jane (as the Devil) asks Tony if he is ready. Tony sees Sarah is still alive and offers to trade his life for hers. The Devil is enraged at his attempt at bargaining and causes the elevator to drop.
Det. Bowden cannot believe what he is seeing. Dwight's walkie talkie drops into the elevator and Tony, realizing he has only seconds, talks to Bowden and confesses why he thinks he's here. Five years ago he hit a woman's car and killed her and her young son. Though racked with guilt, Tony ran off. Det. Bowden realizes Tony killed his family. The Devil looks to take him too just as Sarah dies, but stops himself. He tells Tony "I wanted to take you too" before disappearing. The elevator is found and opened and Bowden is shocked to see the body of Jane is missing. He screams for the building to be searched to no avail.
Tony gives his statement and is taken away by Bowden for the hit and run. Bowden confesses he has been waiting for this moment for five years, to enact his revenge against the person who took his family. However, Bowden says he has forgiven Tony.
There is one final voice over by Ramirez, saying his mother always reassured him after her Devil's stories by saying if the Devil was real, so was God.
Since Bowden was able to forgive Tony for his sin, the Devil couldn't take him to hell and thus saved him from death.