She nabbed the small but pivotal role of "The Thief" in the New York premiere production of Jean Genet's The Balcony. She won excellent notices playing Josie in A Moon for the Misbegotten at the downtown Circle in the Square Theatre in the late 1960s in New York, and she did a Cleopatra at Stratford.
In 1963 Jens appeared in an episode of The Untouchables, "The Man in the Cooler". She appeared in a 1963 episode of The Outer Limits, "Corpus Earthling", and the I Spy episode "A Room with a Rack" in 1967, as a globe-trotting pilot friend of Kelly Robinson and Alexander Scott. She was cast as a prisoner in "The Wagon", a 1970 episode of Bonanza.
Jens was born in Milwaukee, Wisconsin to Salomea (née Szujewska) and Arnold John Jens, a farmer and builder. Jens graduated from Bay View High School with a 96 average and was crowned Miss Bay View at the long-running South Shore Water Frolics. In an article from July 1969, she remarked that "the only time I can imagine contemplating suicide would be if I was told that I had to go back and live in Milwaukee forever", a comment for which she later apologized.
In 1971, she portrayed a widow with two children in the Gunsmoke episode, "Captain Sligo," with Richard Basehart in the title role as an Irish cattle buyer who courts her. In 1974 she guest-starred in an episode of McMillan and Wife, "Reunion In Terror", and on The New Land. She appeared on Gibbsville in 1976. In 1976–77 Jens played the role of Mae Olinski on the soap spoof Mary Hartman, Mary Hartman. She appeared on the scripted talk show Meeting of Minds, hosted by Steve Allen (S03E05 and S03E06, 1979), portraying Empress Theodora.
Jens narrated a number of documentaries including The Great War and the Shaping of the 20th Century and the 1986 film, The Clan of the Cave Bear. She also voiced the female Guardian in the Green Lantern movie (2011).
Jens appeared in a 1993 episode of Star Trek: The Next Generation as an "Ancient humanoid", a member of the race responsible for populating the galaxy with humanoid lifeforms, and had a recurring role spanning 5 seasons of Star Trek: Deep Space 9 as the authoritarian Female Changeling (1994-99).
