Bremer began taking dance lessons at age 7 and at 12 joined the Philadelphia Opera Company's corps de ballet. She became a Radio City Music Hall Rockette at age 16, later dancing in Manhattan nightclubs and in Broadway musical chorus lines. Her short-lived film career began when she was discovered by MGM musical producer Arthur Freed; after some drama coaching she made her film debut in Meet Me in St. Louis (1944). An attractive, smooth redhead, she went on to appear as Fred Astaire's dance partner in two movies; some consider her to be the most talented screen dancing partner Astaire ever had. At first groomed to be a star, she nevertheless failed to make it and her promise was squandered. She was dropped by MGM in 1947 and retired from film in 1948 when she married the millionaire son of the one-time provisional president of Mexico. Her last film was Behind Locked Doors (1948).