When ambitious newspaper reporter Ann Mitchell loses her job in the middle of the Depression, she prints a phony letter from a "John Doe" who, protesting the state of society, promises to jump off the Brooklyn Bridge on Christmas Eve. Circulation goes through the roof, and Ann convinces her editor to hire an out-of-work ballplayer, John Willoughby, to stand in while she ghost-writes the "John Doe" column.
With her words and his down-home charm, John Doe quickly becomes a national sensation. As Ann, John and "John" tour the country, a strange love triangle begins to form. When the paper's powerful owner reveals his true plans for John Doe, both Ann and John must confront the hoax they've created and decide what they truly believe in.