Born in 1938 in London, England as Joanna Venetia Invicta Stevenson, she is the daughter of film director Robert Stevenson and actress Anna Lee. The family moved to Hollywood within a year of her birth after her father signed a contract with film producer David Selznick. When her parents divorced in 1944, she stayed with her father and new stepmother, Frances. After an education in exclusive Californian private schools, her theatrical debut was with her mother in Liliom, a play produced by the Sombrero Theater, in Phoenix, Arizona, in April 1955 and also with the husband and wife team of Fernando Lamas and Arlene Dahl.
A one-time Miss Los Angeles Press Club, Stevenson was placed on contract by RKO Pictures in November 1956. Hedda Hopper named Stevenson on her list of top movie newcomers in January 1957, alongside Jayne Mansfield. Hopper said of Stevenson, then 18, she is "the most purely beautiful of all the new crop of stars.
Film and television
In March 1957, Stevenson was in the cast of the CBS Playhouse 90 adaptation of Charley’s Aunt, alongside Tom Tryon, Jackie Coogan, and Jeanette MacDonald were among the cast in the telecast. Stevenson played Peggy McTavish in Darby’s Rangers, a Warner Bros. release in which she was paired off with Peter Brown. She is one of the women who is pursued by actors cast as members of an American unit of the same name during World War II. The movie was directed by William Wellman.
Stevenson’s publicity machine continued to promote her. She was reported enjoying riding horses as an activity and playing table tennis. In November 1957, she won $300 in prizes at a horse show and participated at the National Horse Show at the Cow Palace in San Francisco. Around this time she became the face on Sweetheart Stout cans and bottles; the brand marked the 50th anniversary of using her image in 2008.
She appeared in the western drama The Day of the Outlaw (1959), starring Robert Ryan and Tina Louise. Stevenson appeared in the English film Jack The Ripper (1960). She also had a primary role, in the film version of the Studs Lonigan trilogy by James Farrell, brought to the screen in December 1960. Among the other motion pictures in which she appears are Island of Lost Women (1959), Jet Over The Atlantic (1959), The Big Night (1960), Seven Ways from Sundown (1960), The City of the Dead aka Horror Hotel (1960), and The Sergeant Was a Lady (1961).
Stevenson appeared on television, in episodes of Cheyenne (1957), Colt .45 (1958), Sugarfoot (1957-1958), 3 episodes, 77 Sunset Strip (1958), The Adventures of Ozzie and Harriet (1958), Lawman (1958), The Millionaire (1959), The Third Man (1959), and Alfred Hitchcock Presents (1960).