Bertini began performing on stages at the age of seventeen she began to perform in the just-born Italian movie production. She had a major role in Salvatore Di Giacomo's melodramatic story Assunta Spina.[2]
She had made over 50 films by 1915[2] including, Histoire d'un pierrot, was under the direction of Baldassarre Negroni in 1913. Gradually she developed her beauty and elegance, plus a strong, intense, and charming personality, which would be the key of her success as a silent movie actress. With Assunta Spina in 1915 she took care of the scripts as well as performing the role of the main character. Bertini was to claim with some support that she was the true director of the film which included novel acting techniques.[2]
She was one of the first film actresses to focus on reality, rather than on a dramatic stereotype, an anticipation of Neorealistic canons. The expression of authentic feelings was the key of her success through many films. She could perform with success the languid decadent heroine as well as the popular common woman. Other important roles were Odette, Fedora, Tosca and the Lady of the Camellias.
In 1920,[3] Fox Film Corporation in Hollywood offered to sign a contract with her, but she refused: she was married to the wealthy Swiss banker Paul Cartier and wanted to move with him to Switzerland. When her husband died, she moved back to Rome, where she would remain until her death.
She stepped into sound movies as well, but in the meantime the Italian cinema had changed greatly (the period of Telefoni bianchi comedies) and entered into a period of crisis with fascism and censorship. It experienced a definite hiatus with World War II.