A Beautiful Mind is a 2001 American biographical drama film about the mathematician John Nash, a Nobel Laureate in Economics, played by Russell Crowe. The film is directed by Ron Howard based on a screenplay by Akiva Goldsman, who adapted the 1998 biography by Sylvia Nasar. In addition to Crowe, the film's cast features Ed Harris, Jennifer Connelly, Paul Bettany, Adam Goldberg, Judd Hirsch, Josh Lucas, Anthony Rapp, and Christopher Plummer in supporting roles. The story begins in Nash's days as a brilliant but asocial mathematics graduate student at Princeton University. After Nash accepts secretive work in cryptography, he becomes liable to a larger conspiracy, through which he begins to question his reality.

John Forbes Nash, Jr., known and published as John Nash, was an American mathematician who made fundamental contributions to game theory, real algebraic geometry, differential geometry, and partial differential equations. Nash and fellow game theorists John Harsanyi and Reinhard Selten were awarded the 1994 Nobel Memorial Prize in Economics. In 2015, he and Louis Nirenberg were awarded the Abel Prize for their contributions to the field of partial differential equations.