Although Tammy Grimes had originated the title role and had won the Tony Award for Best Performance by a Featured Actress in a Musical for her performance, MGM executives wanted Shirley MacLaine for the film. Harve Presnell was the sole member of the original Broadway cast who was invited to reprise his stage role in the film.

Martita Hunt as Grand Duchess Elise Lupavinova.

Fred Essler as Baron Karl Ludwig von Ettenburg.

Vassili Lambrinos as Prince Louis de Laniere.

Harve Presnell as 'Leadville' Johnny Brown.

When her deed makes international headlines, Molly is welcomed home by Johnny and the people of Denver. Setting sail for home aboard the RMS Titanic, she becomes a heroine when the ship sinks and she helps rescue many of her fellow passengers. For the first time in her life, she realizes that someone else's feelings and priorities need to be considered. She initially falls for the charms of Prince Louis de Lanière, but eventually decides she prefers to live with Johnny in Leadville. Molly decides to return to Europe, leaving Johnny behind. Molly's plan to introduce them to the people who formerly rejected her is derailed by Johnny's rough-and-tumble friends, whose unexpected and boisterous arrival ruins the gala party Molly is hosting. She and Johnny go to Europe, where they are embraced by royalty, and the couple return to Denver with their new friends. The Browns and Seamus move into a Denver mansion, and Molly sets out to improve her social status by trying to ingratiate herself with the city's elite, all of whom snub her and her nouveau riche ways. After miner Johnny Brown renovates his cabin, the two wed, and he sells his claim in a silver mine for $300,000. She journeys to Leadville, Colorado and is hired as a saloon singer by Christmas Morgan. Rescued from the Colorado River as an infant and raised by Seamus Tobin, tomboy Molly Tobin is determined to find a wealthy man to marry. Debbie Reynolds was nominated for the Academy Award for Best Actress for her portrayal of Brown. The plot is a fictionalized account of the life of Margaret Brown, who survived the 1912 sinking of the RMS Titanic. The song score was composed by Meredith Willson.

The screenplay by Helen Deutsch is based on the book of the 1960 musical The Unsinkable Molly Brown by Richard Morris.

The Unsinkable Molly Brown is a 1964 American comedy musical western film directed by Charles Walters and starring Debbie Reynolds, filmed in Panavision.

Unsinkable by debbie reynolds