She is known for playing Alice in the 1970s sitcom Soap – one of television's first lesbian characters – as well as for portraying Lucille LaRusso in the films The Karate Kid and The Karate Kid Part III, and in the streaming series Cobra Kai; and Bert Cooper's and Don Draper's elderly secretary Ida Blankenship in a recurring role on the series Mad Men.

[3][4] After initially attending Emerson College in Boston, she returned to Long Island to graduate in 1969 from Adelphi University, where she studied theater.

[6][7][8][9] The Boston Herald said that the characterization shows how "the networks have generally depicted lesbians either as suicidal losers or sexual predators."

For example, it identifies Alice as "TV's first recurring lesbian character," noting that she "first tries to throw herself off a bridge, then falls for Jodie (Billy Crystal), a confused gay man, and finally runs off.".

"[9] Heller would appear as a lesbian character again in a 2010 episode of Grey's Anatomy "Almost Grown," playing the partner of a female patient with a brain tumor.

Heller had a recurring role in the fourth season (2010) of AMC's Mad Men as Bert Cooper's and Don Draper's elderly secretary Ida Blankenship.

When her engagement to her Jewish beau, Herr Schultz, is called off, it symbolizes many of the small human tragedies brought about by Nazi hate.

She performed the role after having been diagnosed with breast cancer the year before and undergoing a double mastectomy and chemotherapy and radiation treatments.