Born Myrna Adele Williams in Raidersburg (near Helena, Montana), she moved to Los Angeles, California when she was young. At the age of fifteen she began appearing in local stage productions, an in 1925 appeared in the movie What Price Beauty. Her silent film roles were mainly those of vampish exotic women, but she was cast in more wholesome roles in talkies. Her performance in The Thin Man as William Powell's sophisticated, witty wife Nora made her a star.
She has a star on the Hollywood Walk of Fame at 6685 Hollywood Blvd.