Nightmare Alley is a 1947 American film noir directed by Edmund Goulding from a screenplay by Jules Furthman. Based on William Lindsay Gresham's 1946 novel of the same name, it stars Tyrone Power, with Joan Blondell, Coleen Gray, and Helen Walker in supporting roles. Power, wishing to expand beyond the romantic and swashbuckler roles that brought him to fame, requested 20th Century Fox's studio chief Darryl F. Zanuck to buy the rights to the novel so he could star as the unsavory lead "The Great Stanton", a scheming carnival barker.

The film premiered in the United States on October 9, 1947, then went into wide release on October 28, 1947, later having six more European releases between November 1947 to May 1954.

As noted on the DVD commentary track by Alain Silver and James Ursini, Nightmare Alley was somewhat unusual among film noir in having top stars, production staff and a relatively large budget. The film was not a financial success upon its original release but has since found acclaim and is regarded as a classic.