The Bells of St. Mary's (1945) is an American musical comedy-drama film, produced and directed by Leo McCarey and starring Bing Crosby and Ingrid Bergman. Written by Dudley Nichols and based on a story by McCarey, the film is about a priest and a nun who, despite their good-natured rivalry, try to save their school from being shut down. The character Father O'Malley had been previously portrayed by Crosby in the 1944 film Going My Way, for which he won the Academy Award for Best Actor. The film was produced by Leo McCarey's production company, Rainbow Productions.

Harry Lillis "Bing" Crosby Jr. was an American singer, actor, television producer, television and radio personality, and businessman. The first multimedia star, he was one of the most popular and influential musical artists of the 20th century worldwide. Crosby was a leader in record sales, network radio ratings, and motion picture grosses from 1926 to 1977. He was one of the first global cultural icons. Crosby made over 70 feature films and recorded more than 1,600 songs.