She was born Betty Gale Russell on September 21, 1924 (some sources say 1921) in Chicago, Illinois. Her father, George Russell, was a musician. The family moved to Los Angeles, California when she was a teenager. At the age of eighteen she was discovered by a talent scout and signed a contract with Paramount for $50 a week. Gail made her film debut in the 1943 comedy Henry Aldrich Gets Glamour. Then she was cast opposite Ray Milland in the horror film The Uninvited. She suffered from severe anxiety during filming and began drinking. The Uninvited was a box-office hit and made her a star. The beautiful brunette was given leading roles in the films Sally O'Rourke, The Unseen, and The Bachelor's Daughters. While making Angel And The Bad Man in 1947 she began an affair with married John Wayne. Gail also had an affair with John Farrow who directed her in Night Has A Thousand Eyes. On August 1, 1949 she married actor Guy Madison. The couple separated after six months but reunited soon after. By the early 1950s her career was in trouble and she was struggling with alcoholism.
She tried to get sober by spending several weeks in a sanitarium. It didn't work and in November of 1953 she was arrested for drunk driving. Then she was hospitalized after an attack of hepatitis. Her tumultuous marriage to Guy came to an end in 1954. Hoping to make a comeback she accepted a role in the 1956 drama Seven Men From Now. Gail said "I want to get back to the business to prove to people I can do a picture. I'm stronger now. The future looks pretty good." In July of 1957 she got drunk and drove her car into a Los Angeles coffee shop. She was arrested and sentenced to three years of probation. Gail began a romance with lesbian singer Dorothy Shay. They broke up after two years together. Her final film was the low budget 1961 drama The Silent Call. Tragically on August 26, 1961 she was found dead in her apartment surrounded by empty vodka bottles. The thirty-six year old had died from liver damage caused by acute alcoholism. She had also been suffering from malnutrition. Gail was buried at
Valhalla Memorial Park
in North Hollywood, California.