Lynn was born in Latvia as Zinta Valda Ziemelis. She and her mother fled in 1944, eventually arriving in the United States in 1950.
Lynn is best known as "Fräulein Helga" in Hogan's Heroes during the first season (1965–1966). She returned to the series in the 1968 and 1971 episodes, "Will the Blue Baron Strike Again" and "Easy Come, Easy Go", respectively. Her last acting role was in 1975 in an episode of Harry O.
Lynn died on March 10, 2014, at age 77, from multiple organ failure after being stricken with hepatitis. She is survived by her daughter with Marlon Brando, Lisa Brando.