Jean Shirley Verhagen, later shortened to Hagen, was born on August 3, 1923, in Chicago, Illinois, to a Dutch immigrant father. At the age of twelve, she moved to Elkhart, Indiana, with her family, graduating from Elkhart High School and subsequently from Northwestern University, where she studied drama and was a roommate of fellow actress Patricia Neal.
Jean Hagen began her show business career in the late 1940s, initially performing in radio programs and later making her way to Broadway plays. Her film debut came in 1949 with a comical femme fatale role in Adam's Rib, starring Katharine Hepburn and Spencer Tracy.
Hagen's breakthrough performance came in 1950, when she starred opposite Sterling Hayden in the film noir classic The Asphalt Jungle, earning her considerable attention and praise. The following year, she lent her support to the classic musical Singin' in the Rain, portraying the helium-voiced silent film star Lina Lamont, earning her an Academy Award nomination for Best Supporting Actress.
After her success in Singin' in the Rain, Jean Hagen joined the cast of the television sitcom The Danny Thomas Show, where she played the role of Margaret Williams, earning three Emmy nominations. However, she grew tired of the role after three seasons and left the show.
For the remainder of her career, Hagen mostly made guest appearances on various television shows, including Alfred Hitchcock Presents, The Andy Griffith Show, Wagon Train, and Starsky and Hutch. She also had supporting roles in Sunrise at Campobello and Dead Ringer.
Sadly, by the 1960s, Jean Hagen's health had declined, and she spent many years under medical care. She passed away on August 29, 1977, at the age of 54, due to esophageal cancer.