Henry Creedlow (Jason Flemyng) is a businessman who wakes up in the morning, and goes through his usual routine, doing things like showering, shaving, and brushing his teeth. He then puts a gun to his head and shoots himself... a fatal act he merely imagined. Henry eats breakfast, working his way around his incomplete house for it is in the mists of construction. He deals with a constantly barking and insubordinate little dog. The dog is actually owned by his high-strung, contemptuous wife Janine (Nina Garbiras) who seems indifferent to Henry.
Henry drives to a local train station where he meets with his best friend, Jimmy Larson (Andrew Tarbet) to go to work downtown. Apparently, Jimmy has invested some money for Henry, and Henry's return is much lower than he thought. While trying to board the train, an unsettled Henry imagines himself pulling away a pushy lady and struggling with her until he puts her head under the railroad tracks, allowing a passing train to crush her head. Waking up from his fantasy, Henry boards the train with Jimmy.
Henry works at a local magazine company called 'Bruiser'. While at the office, everyone is at a conference meeting deciding on which model should be on the magazine's latest issue. The reprehensible boss, Miles Styles (Peter Stormare), mocks Henry's choice in front of him and his co-workers. Later that day, Henry talks with Miles' wife Rosie (Leslie Hope), who works at the lead photographer, and there appears to be an attraction between them as she is the only person who is casually nice to Henry.
Later that afternoon while playing indoor tennis at a local country club with Jimmy, Henry tells his friend that he cannot get a platinum credit card for his assets are coming up short, and his wife is spending his money faster than he makes it. Jimmy convinces Henry that this is only a temporary setback and that profits will come in sooner or later.
That weekend, there is a pool party for the workers at Miles and Rosie's house. The cynical Janine goes off not wanting to speak to the weak-willed Henry, who is sitting for a plaster mold to be made of his face by Rosie whom also designs masks in her spare time. Rosie finishes the mask and adds it to her "garden of lost souls" in the backyard. She asks Henry to paint a design on the featureless mask, but Henry cannot think of anything to draw. Henry sees Miles and his wife across the pool in a very intimate moment.
While driving home later that evening, Henry confronts Janine about what he saw as her making the moves onto his boss. Incredibly, Janine hardly seems to care and she tells the distraught Henry that he is so weak-willed and a pushover, she despises living with him and firmly wishes that he were dead. Janine tells Henry: "You're going no place! You're nothing! You're nobody!" When they arrive home, Henry then has another fantasy about Janine pulling the car into the garage, and him getting out and killing her with an axe to her head. Janine gets back into the car and drives off into the night, leaving Henry all alone.
After drinking all night at his house, Henry awakes up the next morning as usual and goes though his routine, only when he goes to the bathroom mirror to shave, he is shocked when he sees a white-faceless, porcelin mask staring at him. Henry's entire face has inexplicably transformed into a faceless image. When Henry tries removing the "mask" he cuts himself. Henry hides when Katie, his once-a-week maid, arrives to clean the house. Henry watches the maid as she fills her purse and bag with silver and other items from his house. When Katie begins taking cash out of Henry's walet that is left on a counter, Henry reveals himself and confronts his kleptomaniac maid about stealing from him. When Katie admits that she has been pilfering items for weeks now from his house just because she wants to, Henry attacks and beats her to death with the bag filled with stolen silver items. He wraps the body up in plastic and hides again when Janine comes home. Henry overhears a phone conversation in which Janine tells the person on the other line that she is going to leave Henry.
Henry follows his wife to the office where it is revealed that she and his boss, Miles, are having an affair. But it is Rosie who catches them first by bursting into a conference room and photographing Miles and Janine having sex on the conference table. When Miles chases his wife out of the building where Rosie tells Miles that she intends to leave him, Henry sneaks into the conference room where he reveals his new blank face for his wife. When Janine expresses no remorse for cheating on Henry, he attacks her by wrapping her neck around an extension cord and pushes her out a window where she hangs to death.
Miles is distraught over his wife leaving him and of Janine's death. While giving a statement to Detective McCleary (Tom Atkins) whom is the first policeman on the scene, Henry eludes the police and goes home. He hides from the cops again when they come to his front door to look for him to deliver the news of his wife's murder. After Henry finally has had enough of Janine's barking dog, he throws the dog into his refrigerator. While looking through his business files, he discovers that his friend, Jimmy, has more than likely been taking Henry's money for himself. After making it appear that he possibly killed himself and disposes of the maid's body by burying it in the back of his house, Henry phones Rosie and tells her not to go out of her house because he overheard the police who think that she might have killed Janine.
That afternoon, Henry visits Jimmy at the tennis club where he points a gun at Jimmy in the deserted locker room and reveals the business papers which show that Jimmy has been pilfering money out of Henry's bank accounts and mutual funds for years now. Jimmy tells Henry that it was Janine's idea to steal Henry's money so she could squander it for herself. Jimmy reveals that Janine has been cheating on Henry with him too. Jimmy offers to write Henry a check for the entire amount of $30,000, but Henry politely refuses. Then, Jimmy suddenly breaks character by pulling out a gun from his briefcase and tries to kill Henry. Henry fires back, fatally wounding Jimmy in the chest. With his last breath, Jimmy (just like Henry's wife Janine, and the housekeeper Katie), expresses no guilt for his betrayal. Henry hides Jimmy's dead body in the trunk of his car and pushes it into the nearby lake.
The next day, still in the featureless mask, Henry goes to visit Rosie at her home to tell her whats been up lately. ("I've been working on my image".) After he leaves, Henry calls 'The Larry Case Show', a popular radio program, and tells the host that he is 'Faceless' and has murdered three people. After listening to some advice by Larry Case, Henry decides that he needs to eradicate all the people from his life if he is to get his face back.
The following night, Henry goes to attend Miles' costume party, dressed as Zorro wearing a white mask which he blends in perfectly. Rosie is also there who is being tailed by Detective McCleary whom still thinks that she either killed Janine, or had it done. Henry assembles a group of men from the office where they take Miles away to a second floor balcony where Henry tells his mean and ungrateful boss that he has set him up for a grand finale. With the crowd of partygoers underneath, Miles is raised overhead on wires, which people have doing throughout the party. Henry aims a strong laser at Miles (intended for exploded the heads of confetti-filled dummies), and kills him, while the crowd cheers. As Henry walks away, he removes his black cape costume and hat, and his face suddenly returns to normal. Henry realizes that he has his face back when someone walks by and calls his name out. But he is also spotted by Detective McCleary who moves into apprehend him for the killings. However, Rosie shows up in the Zorro costume with a white mask on and yells at McCleary that she's the killer. Rosie tells Henry that she made a plaster of her own face and it was blank, just like Henry's. Now that his revenge is complete, he has his face back and he can start a new life for himself. Henry is then lost in the crowd and McCleary cannot get to him. Henry bids Rosie farewell and escapes into the crowd.
Some years later, a long-haired Henry is now working as an office messenger boy in another city. Henry passes by an office where an angry and loathsome executive is yelling at several people. After the man screams at the overly curious Henry who walks by, the mean executive tells him to come back to his office for he has a job for him. "Coming sir", says Henry in an angry tone who turns around... and his blank, anonymous, faceless white mask has returned.