Lawrence's career began as a child photographer's model. She appeared in her first film, Billy Rose's Diamond Horseshoe (1945), as a night-club patron. A year later, she made a strong impression in her second film at 20th Century-Fox, Margie, in which she played outgoing flapper Maryville. She was featured in the swashbuckler Captain from Castile (1947) with Tyrone Power. While finishing her studies at UCLA, she attracted the attention of talent scouts, and Lawrence was soon featured in a number of additional 20th Century-Fox movies, including You Were Meant for Me, Give My Regards to Broadway, A Letter to Three Wives, The Street with No Name, and Thieves' Highway. At Universal in the early 1950s were Peggy and Here Come the Nelsons. She also was one of the stars of Columbia Pictures' romantic comedy, Paris Model, in 1953.