NOTE: This spoiler was sent in by Marcus.

The film begins with security guard Gary Lewis (Josh Cole) running through a subway station. He’s clearly frightened of something, and he uses a fire extinguisher to break a door open. He enters and winds up in a locker room. He tries to escape through the window, but finds that it doesn’t lead to anywhere. Suddenly, the lockers all start to open and they all have mirrors inside. Gary’s reflection is cast in all the mirrors, and then he sees a big mirror on the wall. He says that he wasn’t trying to escape, and says that he doesn’t want to die. The mirror starts to crack and Gary desperately tries to clean up the cracks when a shard of glass falls onto the floor. Gary apologizes and bends down to pick up the shard. Then he sees that his reflection is remaining standing and is looking down at him. His reflection, holding the shard of glass, stabs himself in the throat and slits his throat open, spraying blood all over the mirror. Gary’s throat is slit open and he dies while his reflection smiles at him.

Next, we see Ben Carson (Keifer Sutherland) wake up in his bed. After taking a shower, he takes some pills and gets dressed. We see from newspaper clippings he has that he used to be a police detective, but was suspended after he accidentally killed an undercover cop. He now lives with his younger sister Angela. Ben gives Angela (Amy Smart) a quick hi-and-bye before leaving for work. He walks the streets of New York until he gets to a locked door. He rings the buzzer, and Lorenzo Sapelli (John Shrapnel) opens the door for him. Lorenzo is the day shift security guard for the Mayflower department store, and Ben has been hired as the new night shift guard. Lorenzo shows Ben around the store while informing him of the store’s history. The Mayflower store used to be one of the best stores in New York, but it was set on fire five years ago. Currently, there’s a lawsuit with the insurance company, and so the store remains unrepaired (which also means that there is no electricity). Mayflower has hired security guards to patrol the premises every couple of hours. When they get to the women’s section of the store, Ben remarks that all the mirrors look so clean. Lorenzo says that the last security guard, Gary Lewis, was obsessed with the mirrors and cleaned them every night, which is why they are spotless. Lorenzo also shows Ben the security trailer outside the store, which does have electricity and a TV in case he gets bored.

Later on, Amy Carson (Paula Patton), Ben’s estranged wife, arrives home with groceries and hands them off to her maid Rosa (Aida Doina). Rosa tells Amy that Ben has come home. Amy walks upstairs and sees Ben playing with his son Michael (Cameron Boyce) while his daughter Daisy (Erica Gluck) talks to him about her day. Amy asks to speak with Ben alone. Ben kisses his kids and wishes Michael a happy birthday while also telling him to get ready for his bath. Amy and Ben walk into the bedroom, where Amy gets upset that Ben didn’t call before coming over. He says that he would’ve if she actually talked to him on the phone. They argue with each other and Ben has a violent outburst, slamming the walls in anger that he has to ask permission to come and wish his son a happy birthday. Meanwhile, Michael hears all the shouting in the bathtub and covers his ears. Ben apologizes for his outburst and says that he’s trying to get back on his feet. He asks Amy if they can get back together again, and they kiss each other. Amy pulls away and says no, since his mood swings make him unpredictable and she doesn’t want him around with his temper.

At night, Ben goes to work and stays in the security trailer. He makes some tea and opens a cupboard to find a whiskey bottle. Although tempted, he doesn’t have any and sits down to watch TV. His alarm goes off, and so he enters the store to check the perimeter. Ben walks through the store and everything seems fine, though he does get startled by a bird. He looks into a mirror and sees a handprint appear. He tries to rub it off, but it won’t go away. He then sees several more handprints appear all over the mirror, and he sees in the reflection that the door behind him is opened. Ben turns around and sees that the door is closed, but in the mirror it’s open. Confused, he opens the door and sees that there’s a basement inside. Ben goes down the stairs and sees that the basement is flooded with water. The next day, Ben wakes up and goes to the bathroom to take his pills. Angela sees him and tells him that he shouldn’t be taking them. Ben tells her to go away and drinks some water with his pills. When he looks into the mirror, he sees that his reflection is distorted and his face appears to be drooping. Startled, Ben falls back and Angela asks him what’s wrong. He yells for her to get out of the bathroom and leave him alone. Ben looks into the mirror and sees that his reflection is normal, though he is clearly confused as to what just happened.

Ben goes back to work and patrols the store at night. He again sees a handprint appear on a mirror, and when he puts his hand on it the mirror cracks, slicing his hand. A short while later, he looks into a mirror and is startled by the sudden appearance of someone on fire in back of him. When he turns around, he doesn’t see them, but he sees their reflection in the mirror. Ben’s reflection is then set on fire and screams in pain as he is burned alive. We then see Ben on the floor, reacting as if he really was on fire. He gets up and is unharmed. On his way out, he sees a wallet nearby and picks it up. Ben goes back to the security trailer and bandages his hand. He looks through the wallet and sees that it belongs to Gary Lewis. Hidden in the cash is a piece of paper with a single word on it – “esseker”. Later on, Ben goes to a bar where Angela works as a bartender and he tells her what he saw in the mirrors. He says that he actually felt the heat of the flames on him, and he feels as though there’s someone or something on the other side of the mirrors that looks back whenever he looks into one. Angela reassures him that there’s nothing in the mirrors, and tells him to get some rest.

The next night, Ben goes to work and hears screaming coming from within the store. He searches around but doesn’t find anyone. He eventually makes his way to the women’s dressing room, and then the screaming stops. He searches through all the stalls but finds no one. He then looks into a mirror and sees someone’s arm sticking out of one of the stalls. Scared, he turns around but doesn’t see anything. Fed up, he drags the mirror over to the center of the room and positions it in front of the stall. He sees the reflection of a woman convulsing on the floor. He opens the stall again and sees via the mirror that a burnt woman with an exposed breast is on the floor, screaming as her skin bubbles up. Michael wakes up in his room and screams for his mother. Amy comes in and Michael says that he had a nightmare about a burnt woman screaming at him. She tells him that it was just a dream and to go back to sleep. She leaves and keeps the bedroom door open. Michael looks into the mirror in his room and sees the burnt woman standing inside, looking at him. Michael, scared, pulls the blanket over his face.

Ben visits Lorenzo at work and asks him what happened to Gary Lewis. He says that Gary quit, and the police just recently found him dead in a subway station. Ben asks how he died, but Lorenzo doesn’t know. Somewhere along here, Ben is at home when he gets a package. He sees that it’s from Gary Lewis. Baffled, he opens the package and finds numerous newspaper clippings about the Mayflower store and the big fire that happened five years ago. At a hospital, Amy is busy performing an autopsy when Ben shows up. She’s agitated that he’s there, but he asks to see Gary’s body. Amy won’t let him, but Ben is adamant that it’s extremely important that he knows how he died. Amy brings Ben to the morgue and opens up the drawer that has Gary’s corpse on it. The report says that he slit his own throat with a shard of mirror. While Ben looks at Gary’s body, he sees Gary’s head in a reflection turn and stares at him. Ben freaks out, but Amy doesn’t know why since she didn’t see anything. Ben begs for her to allow him to see Gary’s file, since he sent him a package before he died, and he knows he was trying to warn him of something. Amy gives him the file and Ben notices that in one of the pictures, it shows Gary’s body in front of a mirror. The strange thing is that in the reflection, the shard of glass is bloody, but outside the mirror the shard is bloodless. Amy says that Ben’s just seeing things because of the strong pills he’s taking to overcome his alcoholism.

Later on, Angela stands in her bathroom and looks at herself in the mirror while she ties her hair in a knot. She disrobes and gets in the bathtub, but her reflection remains standing, staring angrily at her. Her reflection shoves her hands into her mouth, forcing it open. Angela, in the tub, suddenly feels her mouth being pried open. Her reflection then slowly rips off her lower jaw, and the same thing happens to Angela in the tub. Angela thrashes around as her jaw is ripped off, and she painfully dies. The police arrive and set up the crime scene. Detective Larry Byrne (Jason Flemyng) inspects Angela’s corpse and is taken aback by the brutality of it. He unplugs the bathtub to allow all the bloody water to drain out. While the cops interview the neighbors, Ben shows up and tries to enter the apartment but is held back. He asks Larry where Angela is, but Larry tells the other officers to keep him out. Ben shoves them away and forces himself inside the bathroom. Ben sees his sister’s dead body, vomits in the sink, and cries in agony. Angela’s body is brought to the morgue at the hospital, and Larry brings up that Ben was a suspect, but his alibi checked out. Amy says that he would never hurt his sister, since he took care of her after their father died. Ben holds Angela’s hand, and Amy says that he can come home with her and be with the kids. Ben says that he has to go, since he knows who killed Angela.

Ben goes back to the Mayflower store and tries to break down the mirrors with a chair, but it has no effect on it. In a fit of rage, Ben pulls out his pistol and unloads an entire clip into the mirror. The bullets cause the mirror to crack, but then the mirror smoothes itself out, looking as though nothing happened to it. Ben screams “what do you want?” at the mirror, and then he sees that it scratches a word onto itself. The word is “esseker”. Ben goes back to his apartment and looks through the newspaper clippings that Jerry sent him. As he does so, he calls Larry and asks him to run the name Esseker through the police files. Larry’s search turns up nothing, and so Ben has him search the name Terrence Barry, since he’s the man responsible for the Mayflower store fire. It turns out that Terrence was a security guard who strangled his wife and drowned his three kids, but he always blamed the mirrors for the deaths of his family (which is why he set the store on fire). Ben finds out that Terrence was sent to a mental hospital briefly before he died. Ben goes to the hospital and sees Terrence’s old doctor, who shows Ben a videotape of one of his interviews with Terrence. Terrence (Ezra Buzzington), horribly burned from the fire, said that there’s something evil in the mirrors. They tried to get him to find someone named Esseker, and when he failed they slaughtered his family. Ben realizes that his family is in danger and rushes off to his house. Rosa calls Amy and tells her that Ben is moving all the furniture.

Ben removes all the mirrors from the house and places them outside. For the mirrors that can’t be moved (like the ones on the walls or behind the doors), he uses green paint to cover them up. Amy goes home and tells him that he’s acting crazy. She doesn’t believe him when he says that there’s something in the mirrors, and so he takes her to the front of the house. Ben shoots one of Daisy’s mirrors four times, but it doesn’t heal itself up again, causing Ben to look crazy. Ben, confused, walks into the middle of the street while holding his gun. His kids watch from inside the house, and Amy tries to get him to go back inside so that they can talk this over. Ben apologizes and drives away. On the highway, Ben looks into the rearview mirror of his car and sees Angela’s reflection in the mirror, minus her jaw. Ben freaks out, almost gets into a car accident, and destroys his rearview mirror. Ben goes back to the basement of the Mayflower and goes to the end of it. He breaks his way through a wall and finds a hidden room inside. The room has a bunch of mirrors circling a seat in the middle. Ben looks at the mirrors and finds that there are several reflections of him projected. While his back is turned, one of his reflections turns around and looks at him. Ben turns around but doesn’t see anything odd. He then sees one of his reflections smiling at him and shooting at him with his pistol. Ben screams and puts his arms up, but finds that he is unharmed. He leaves the room and on his way out he sees an inscription, which states that the room was part of a mental hospital.

Ben contacts Larry and asks him to find where the hospital files are. Later on, Ben meets Larry outside the police station and Larry gives him all the files he could find. Apparently, long before the Mayflower was a store, it was a mental hospital. There was a twelve year old patient named Anna Esseker, who suffered from schizophrenia and violent outbursts. She was brought to the hospital to be under the care of a doctor, but then one day all the patients slaughtered each other, including Anna. The hospital was thus closed down and it was turned into the Mayflower. The doctor was later found dead, and it appeared as though he slit his wrists with a piece of mirror. Ben goes home and looks over Anna’s file, seeing that all her pictures are blurry. Ben, however, does find a discrepancy in the files. One report says that she was at the hospital when all the patients were killed, but another report says that she was released two days before the slaughter. Ben walks over to a covered up mirror and shows it Anna’s picture. The mirror cracks, and Ben realizes that she’s still alive and the mirrors want her for some reason. The back of the picture shows that it was taken in Pennsylvania, and so he decides to travel there.

Meanwhile, while Daisy brushes her teeth, Amy hears Michael talking to someone in his room. She opens the door to find him talking to himself in the mirror (which was only half-painted before Ben left). Michael leaves the room, but his reflection remains in the mirror, which scares Amy. She walks over to the mirror and sees Michael’s reflection smiling at her. She calls Ben and tells her that there’s something in the mirrors. He races home and finishes painting the mirrors. Amy helps, and they also cover up all the windows with newspapers and put away all the framed pictures (basically anything that can cause a reflection). Ben tells her to stay in the house with the kids, since it’s the safest place now while he goes to Pennsylvania to track down Anna Esseker. Amy tells him to do whatever it takes to save their family. They kiss one last time before Ben leaves. He drives to Pennsylvania, and comes upon a side road. He decides to take it, since the mailbox says that it belongs to Esseker. Ben drives up to the house and asks to speak with Anna. The boy who answered the door gets his grandfather and it turns out that the old man’s sister was Anna. Ben says that he’s writing a paper on schizophrenia and would like to know more about Anna. The old man takes Ben down into the basement, where they kept her locked up like an animal because she would constantly attack them. They were convinced that she was possessed by a demon, and one day a doctor heard about her case. He convinced the family to bring Anna to the mental hospital. The old man says that Anna died in the massacre, but Ben calls him out on his lie. He eventually tells Ben that they picked her up two days before the hospital killings, and they dropped her off at a monastery nearby.

Ben drives to the monastery and requests to speak with Anna. Ben is brought to a room that is divided by a screen. Anna Esseker (Mary Beth Peil), now a nun, is seated behind the screen. Ben tells her about the mirrors, and says that it’s been killing off all the security guards because they’ve failed to find her. He wants to know why the mirrors want her. Anna says that she was possessed by something evil when she was young, and she was strapped to the chair surrounded by mirrors to treat her schizophrenia for days on end (the idea being that it forced her to confront her image). During one of the sessions, the evil left her and entered the mirrors. Whoever the mirrors kill, or whoever dies in the building, remains trapped in the mirror world. The evil wants Anna back so that they can repossess her. Ben begs her to come back to New York with him, since his family will be killed if he doesn’t bring her. He even gives her a picture of his family, but she refuses, saying instead that she’ll pray for them. Back at the house, Michael’s reflection opens the doorknob to Amy’s bedroom. Ben calls Amy and tells her that Anna won’t come back with him. Amy realizes that Michael is missing and goes into the hallway, leaving Daisy by herself on the bed. Amy sees that the house is being flooded by water, and that the paint on the mirrors has been scratched out by someone. Amy accidentally drops the phone in the water, and Ben grows desperate. He forces his way into Anna’s room and holds her at gunpoint, telling her that his family is not going to die tonight.

Amy goes into the bathroom to turn off the water. She looks into the bathtub and sees Michael’s reflection in the water. She turns around but doesn’t see him, and her head is suddenly forced underwater. While Amy is being drowned, Daisy hears Amy calling out for her. Daisy follows the voice to Michael’s room and sees Amy’s reflection in the mirror. Daisy asks her what she’s doing in the mirror, and Amy tells her to come closer while holding a pair of scissors in her hand. When Daisy is close enough, Amy’s reflection grabs her. In the bathroom, Amy manages to save herself by draining the bathtub of the water. She then goes into Michael’s room just in time to see her reflection cutting Daisy’s neck with the scissors. Amy grabs Daisy away and takes her to the closet of her bedroom. Her reflection watches and then disappears. Amy bandages Daisy’s neck and tells her not to leave the closet for anything. Amy closes the door and goes downstairs to look for Michael. Meanwhile, Ben and Anna arrive at the Mayflower store. As they walk through it, the evil presses up against the mirrors, being drawn to Anna. Back at the house, Amy gets to the kitchen and finds that all the sinks are overflowing with water. She shuts off the water and handprints appear on the windows. She then finds Michael sitting on a ledge, scratching off the paint on the mirrors with a knife. Amy tells him to drop the knife, but he won’t. He says that they just want to play with them, and he runs away from her. Amy loses him again, but sees his reflection coming from underneath a table. She tells him that he doesn’t need to hide from her. She touches Michael’s reflection, and it slices Amy’s face with the knife. Amy goes upstairs and finds Michael sitting on the wet floor, stroking his hand in the water. Amy tries to get him to come with her, but he’s suddenly pulled through the water by his reflection. Amy tries to get to him, but it’s helpless as he is being drowned by his reflection and she can’t reach him.

Ben and Anna go to the basement of the Mayflower. Ben straps Anna in the chair that’s surrounded by mirrors. She closes her eyes for as long as she can while Ben stands outside the room, his gun in his hand. As Anna is in the chair, the evil starts to break out of the mirrors and it enters her body. Anna opens her eyes, which causes all the mirrors to explode and sends glass flying all over the place (which cuts her up). Michael is freed due to the mirrors being destroyed, and Amy gives him CPR. She is able to revive him and save him. Meanwhile, Ben enters the room but doesn’t find Anna. He hears her screeching up above and he sees that she’s possessed by the evil. He tries to shoot her but keeps missing. Anna throws Ben through the brick wall and thrashes him all over the place. When Ben is finally able to get up, he finds that Anna has disappeared again. Anna crawls on the walls to get to him, and she starts to drag him away. Ben kicks himself free and manages to impale Anna on a broken gas pipe. He then shoots at the gas pipe, causing an explosion to engulf Anna with flames. The explosion knocks Ben back, and it also causes the basement to start to collapse. Ben tries to escape, but is attacked by Anna (who’s now on fire). He tosses her aside and she’s crushed to death by falling debris. Ben almost makes it to the exit, but he too is crushed by falling debris.

The next morning, Amy holds her two kids close and cries. Ben wakes up and stumbles out of the rubble of the basement. Bloodied, he walks through the Mayflower and sees that the police, ambulances, and fire trucks are already there. Ben sees Lorenzo and walks over to him, but then he notices his name tag. Lorenzo’s name tag is seen reversed, as if seen through a mirror. Ben looks around and sees that all of the writing on the vehicles is reversed. Shocked, he walks through the streets and no one notices him. The newspaper stands are also seen to be reversed. Ben walks to a mirror and places his hand on it. The film ends with his handprint appearing on the mirror while people walk by without noticing (in other words, Ben died in the basement and is now stuck in the mirror world).