Infuriated at being told to write one final column after being laid off from her newspaper job, Ann Mitchell (Barbara Stanwyck) prints a letter from a fictional unemployed "John Doe" threatening suicide on Christmas Eve in protest of society's ills. When the letter causes a sensation among readers, and the paper's competition suspects a fraud and starts to investigate, editor Henry Connell (James Gleason) is persuaded to rehire Mitchell, who schemes to boost the newspaper's sales by exploiting the fictional John Doe. From a number of derelicts who show up at the paper claiming to have written the original letter, Mitchell and Connell hire John Willoughby (Gary Cooper), a former baseball player and tramp in need of money to repair his injured arm (by Bonesetter Brown), to play the role of John Doe. Mitchell starts to pen a series of articles in Doe's name, elaborating on the original letter's ideas of society's disregard for people in need.