The Man Who Wasn't There is a 2001 neo-noir crime film written, directed, produced and co-edited by Joel and Ethan Coen. It stars Billy Bob Thornton, Frances McDormand, Michael Badalucco, Richard Jenkins, Scarlett Johansson, Jon Polito, Tony Shalhoub, and James Gandolfini. The film is set in 1949 and tells the story of Ed Crane, a withdrawn barber who leads an ordinary life in a small California town with his wife, who he suspects is having an affair with her boss. Crane's situation changes when a stranger comes to the barbershop and offers him the opportunity to join him as a partner in a promising new business, in exchange for an investment of ten thousand dollars. Drawn to the idea, Crane plans to blackmail his wife's lover for the money.

The film is in black-and-white and employs voiceover narration, honoring classic film noir. It differs by including classical music, setting the plot in a small town, and featuring a protagonist from outside the criminal underworld. The Coens began developing the idea from a 1940s haircut poster they saw while filming The Hudsucker Proxy. The plot was influenced by James M. Cain's crime novels, primarily Double Indemnity, The Postman Always Rings Twice, and Mildred Pierce. Aesthetically, The Man Who Wasn't There was inspired by films from the 1940s and 1950s—including Shadow of a Doubt—along with science fiction films and documentaries of the period.

Filming took place on location in California. It was shot in color and later converted to black and white. The film premiered and participated in the official selection at the 2001 Cannes Film Festival, where Joel Coen won the award for best director. Its theatrical response was lukewarm, although it was well-received by film critics, who praised Roger Deakins' cinematography and the performances, especially Thornton's. Media critics in The Guardian, the BBC, and The Austin Chronicle referred to it as one of the best films of the year. The National Board of Review included it among its top ten films of the year and awarded Thornton best actor. Deakins received a nomination for the Academy Award for Best Cinematography and the film achieved multiple nominations and awards from other organizations.