The widow of comic actor Tom Poston, Pleshette died of respiratory failure Saturday evening at her Los Angeles home, Robert Finkelstein, an entertainment lawyer and family friend, told the Associated Press. Pleshette underwent chemotherapy in 2006 for lung cancer.
She also appeared with Troy Donahue, to whom she was married for eight months in 1964, in the 1962 romantic drama "Rome Adventure" and the 1964 western "A Distant Trumpet."
On Broadway in 1961, Pleshette replaced Anne Bancroft in the role of Annie Sullivan in "The Miracle Worker," opposite Patty Duke as Helen Keller.
And on television in 1991, she earned an Emmy Award nomination for the title role in the TV movie "Leona Helmsley: The Queen of Mean."
But she had a flair for comedy.
Among her screen credits are "40 Pounds of Trouble," "If It's Tuesday, This Must Be Belgium," "Support Your Local Gunfighter," "The Shaggy D.A.," "The Adventures of Bullwhip Griffin," "The Ugly Dachshund" and "Blackbeard's Ghost."
Pleshette, however, is best remembered for playing what New York Times critic Frank Rich once described as "the sensible yet woolly wife" on "The Bob Newhart Show," which ran from 1972 to 1978. Her role as Emily earned her two Emmy nominations.
Pleshette retired from acting after marrying her second husband, wealthy businessman Tom Gallagher, in 1968. She told TV Guide in 1972 that after she'd been hanging around the house for six months, "my loving husband said, 'You're getting to be awfully boring. Go back to work.' "
After trying to figure out how she could return to work without having to get up at 5 a.m. or go out of town for weeks on movie locations, she recalled, "I said to myself, 'What can you do best?' 'Talk,' I said. 'So what better than the talk shows on TV?' I said. I picked up the phone and asked my agent to try to book me with Johnny Carson."
She made a couple of dozen appearances on the Carson show over the next few years, including one with fellow guest Newhart -- a show seen by writers David Davis and Lorenzo Music, the creatorsof the upcoming Newhart show.
"Suzanne started talking, and I looked at Lorenzo and Lorenzo looked at me," Davis told TV Guide. "There she was, just what we were looking for.
"She was revealing her own frailties, talking freely about being over 30. She was bubble-headed but smart, loving toward her husband but relentless about his imperfections. We were trying to get away from the standard TV wife, and we knew that whoever we picked would have to be offbeat enough and strong enough to carry the show along with Newhart. We didn't dream Suzanne would accept the part."
Pleshette told the magazine that "Bob is just like my husband, Tommy, letting me go bumbling and stumbling through life. And the way it's written, the part is me. There's the stream of non sequiturs by which I live. There are fights. I'm allowed to be demonstrative. But the core of the marriage is good."
Off-camera, Pleshette was known for being what an Orlando Sentinel reporter once described as "an earthy dame, an Auntie Mame who isn't afraid to tell a dirty story." Or, as TV Guide put it in 1972: "Her conversations -- mostly meandering monologues -- are sprinkled with aphorisms, anecdotes, salty opinions and X-rated expletives."
She enjoyed talking so much that during the making of "The Geisha Boy," Lewis took to calling her "Big Mouth."
Newhart, according to the TV Guide article, "was finding himself outtalked by Suzanne on the set about 12 to 1 but professed to be unperturbed by the phenomenon."
"I don't tangle," Newhart said, "with any lady who didn't give Johnny a chance to exercise his mouth -- even to sneer -- for 10 whole minutes."