Yolanda and the Thief is a 1945 American Technicolor MGM musical-comedy film set in a fictional Latin American country. It stars Fred Astaire, Lucille Bremer, Frank Morgan, and Mildred Natwick, with music by Harry Warren and lyrics by Arthur Freed. The film was directed by Vincente Minnelli and produced by Arthur Freed.

The film was a long-time pet project of Freed's to promote his lover Bremer's career, but fared disastrously at the box office. An attempt to create a whimsical fantasy, it ended up, in the words of critic John Mueller, as "egg-nog instead of the usual champagne". Despite admirable production values, it ruined Bremer's career and discouraged Astaire, who decided to retire after his next film, Blue Skies.

Perhaps it also vindicated Astaire's own horror of "inventing up to the arty"—his phrase for the approach of those who would set out to create art, whereas he believed artistic value could only emerge as an accidental and unpremeditated by-product of a tireless search for perfection. In his autobiography, Astaire approvingly quotes Los Angeles Times critic Edwin Schallert: "'Not for realists' is a label that may be appropriately affixed to Yolanda and the Thief. It is a question, too, whether this picture has the basic material to satisfy the general audience, although in texture and trimmings it might be termed an event." Astaire himself concluded, "This verified my feeling that doing fantasy on the screen is an extra risk."

In the pastoral country of Patria, young Yolanda Acquaviva celebrates her birthday in a convent among her fellow students. She has turned 18, and must now take over management of her family fortune, formerly overseen by her Aunt Amarilla. Yolanda feels unprepared, but the mother superior assures Yolanda that her guardian angel will watch over her.

Meanwhile two American con men, Johnny Riggs and Victor Trout, have come to Patria because it has no extradition laws. On the train ride through the Patrian countryside, they learn of the vast Acquaviva fortune from a waiter. They are shown a newspaper reporting on the young heiress, Yolanda. They speculate on how they might take advantage of this opportunity.

Yolanda is greeted at her estate by Aunt Amarilla and many servants. Later, alone in the garden, Yolanda says a prayer to her guardian angel asking for guidance. Unseen by her, Johnny overhears.

Johnny telephones Yolanda, claiming to be her guardian angel. He tells her that he will help her but cannot appear in angelic form. He will meet her in human disguise. The naive girl agrees. At their meeting he tells her to call him Mr. Brown. He claims that he will take away the burden of her wealth. She is easily deceived and agrees to his plans.

Johnny dreams about Yolanda and it unsettles him. Nonetheless, Johnny sticks to the plan with his partner to steal valuable bonds from the accommodating Yolanda. They succeed but run into difficulty in escaping. The situation throws Johnny and Victor together with a third gentleman, Mr. Candle. Candle claims to want what is best for Yolanda. Johnny realizes that he wants this too and returns the bonds. Yolanda has become enamored with Johnny. Believing himself undeserving, Johnny tries to leave the country. Mr. Candle stops Johnny and reveals himself to be Yolanda’s true guardian angel. He wants Johnny to return to Yolanda as a reformed man. In the end Johnny marries Yolanda.