'He was not terribly pleased': Set secret revealed years after Get Smart's end by Barbara Feldon

Hands up if you can't hear the words "good thinking" without immediately thinking "...99"?

Barbara Feldon was one of the leading TV icons of the '60s, thanks to her role as Maxwell Smart's more capable sidekick Agent 99 in the comedy series Get Smart.

She initially rose to prominence as a fashion model, however, memorably appearing in a TV advertisement for Revlon.

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Interestingly, Feldon had been a contestant on iconic quiz show The $64,000 Question in 1957 and won the major prize.

Feldon had initially hoped to be a Broadway star, and she did end up acting. She had small roles in some of the most notable TV shows of the '60s, including The Man from U.N.C.L.E. and Flipper.

Feldon's big break came in 1965 with Get Smart, which aired for five years until 1970 and became one of the defining series of the era (thanks in no small part to its influence on the vernacular of the time – "missed it by that much!", anyone?)

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The series, a spoof on the James Bond-style spy genre, written by Mel Brooks and Buck Henry, was a huge hit and earned the actress two Emmy nominations.

Speaking to Forbes in 2016, Feldon revealed she began taking off her shoes and slouching during filming because she felt "intimidated" being taller than co-star Don Adams – and it seems he wasn't fond of the height difference, either.

"When we did the pilot and first stood on our marks, he looked up and saw me. He was not terribly pleased," she recalled.

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To mitigate the situation, she began working barefoot, joking, "I think I was the only actress in Hollywood who had calluses on her ankles."

"When we walked into a room together, I was taller. But by the time we got to the close-up, I was two inches shorter due to my ability to slouch really effectively."

While Get Smart was on air, Feldon landed some movie roles, most notably in Fitzwilly alongside Dick Van Dyke.

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The actress found herself with plenty of TV role offers when the beloved series eventually ended, but said they all felt like variations on the character of 99 and she yearned for more.

"I want to play a flesh and blood woman. What we're working on is a comedy about a woman who is a mature person. Mary Tyler Moore has broken the ice – that's a mature woman she plays," she told Closer magazine.

"But is there room for more? Is television ready for us? I want to play a thinking woman's woman. A woman who is really into things."

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Feldon reprised the role of Agent 99 twice, for the TV movie Get Smart Again and for another short-lived revival series, Get Smart.

She continued acting on the screen and stage for many years, with roles and guest roles in numerous TV shows – including a one-episode appearance in Cheers – and in three movies, plus further appearances on TV quiz shows.

She's also a published author, having written the book Living Alone and Loving It: A Guide to Relishing the Solo Life in 2003.

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Feldon has effectively retired from acting and lives in New York, having moved back there in 1980 after leaving Hollywood.

She's now 91 years old.

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