The Professor and the Madman is a 2019 biographical drama film directed by Farhad Safinia (under the pseudonym P. B. Shemran), from a screenplay by Safinia and Todd Komarnicki based on the 1998 book The Surgeon of Crowthorne (published in the United States as The Professor and the Madman) by Simon Winchester. It stars Mel Gibson, Sean Penn, Natalie Dormer, Eddie Marsan, Jennifer Ehle, Jeremy Irvine, David O'Hara, Ioan Gruffudd, Stephen Dillane, and Steve Coogan.

The film is about professor James Murray, who in 1879 became director of an Oxford University Press project, The New English Dictionary on Historical Principles (now known as the Oxford English Dictionary) and the man who became his friend and colleague, W. C. Minor, a doctor who submitted more than 10,000 entries while he was confined at Broadmoor Criminal Lunatic Asylum at Crowthorne after being found not guilty of murder due to insanity.

Shot in Dublin in 2016, the film became part of a legal battle between Gibson and Safinia against Voltage Pictures, delaying its release until 2019 and resulting in the pair disowning the final product.