A Song Is Born (also known as That's Life),[4] starring Danny Kaye and Virginia Mayo, is a 1948 Technicolor musical film remake of Howard Hawks' 1941 movie Ball of Fire with Gary Cooper and Barbara Stanwyck.

This version was also directed by Hawks, based on the story "From A to Z" by Billy Wilder and Thomas Monroe, adapted by Harry Tugend (uncredited) and produced by Samuel Goldwyn and released by RKO Radio Pictures.

Other notable musicians playing themselves in the cast include Charlie Barnet (with Harry Babasin as cameo), Mel Powell, Louis Bellson, The Golden Gate Quartet, Russo and the Samba Kings, The Page Cavanaugh Trio, and Buck and Bubbles.

Thanks to two window washers (Buck and Bubbles) seeking help with a radio quiz, they discover that there are many forms of popular music—including swing, jive, jump, blues, two-beat Dixie, boogie woogie, and bebop—that they know nothing about.

She needs a place to hide out from the police, who want to question her about her gangster boyfriend Tony Crow (Steve Cochran).

While there, she introduces them to the latest music, of which they are completely ignorant, aided by many of the musicians Hobart met the night before.

Smitten, the innocent Hobart (who graduated from Princeton at age 13) scours the city for an open jewelry store so he can buy an engagement ring.

The finale, of course, is not decided by guns but by music, its resonance and reverberation, as, inspired by Joshua Fit the Battle of Jericho, the musicians send a drum crashing on one of the henchmen and a professor pulls the rug out from under the other.

When speaking of the film, he said "Danny Kaye had separated from his wife, and he was a basket case, stopping work to see a psychiatrist [every] day.