[5] Dolores M. Heft was born in Chicago, the daughter of an automobile dealer.

[7] Before appearing in films, Dorn acted with the Shaffner Players in Illinois, Iowa, and Missouri.

[8] She appeared in Hide and Seek (1957) on Broadway[9] and in the off-Broadway production Between Two Thieves.

She played the wife of Alan Ladd in the actor's last Hollywood film in which he played a leading-man role, 13 West Street, and was featured as Cuddles, the moll of convict Cliff Robertson, in the crime film Underworld, U.S.A. Dorn appeared in a number of made-for-TV films and as a guest star in series such as Ironside, Charlie's Angels, Simon & Simon, Run for Your Life, and The Untouchables.

Dorn was married to actors Franchot Tone (1956–1959),[12] and Ben Piazza (1967–1979).