The show was inspired by the success of The Man from U.N.C.L.E.. Talent Associates commissioned Mel Brooks and Buck Henry to write a script about a bungling James Bond-like hero. Brooks described the premise for the show they created in an October 1965 Time magazine article:

"I was sick of looking at all those nice sensible situation comedies. They were such distortions of life. If a maid ever took over my house like Hazel, I'd set her hair on fire. I wanted to do a crazy, unreal comic-strip kind of thing about something besides a family. No one had ever done a show about an idiot before. I decided to be the first."

Brooks and Henry proposed the show to ABC, where network executives called their show "un-American", and demanded a "lovable dog to give the show more heart", and scenes showing Maxwell Smart's mother. Brooks strongly objected to their latter suggestion:

"They wanted to put a print housecoat on the show. Max was to come home to his mother and explain everything. I hate mothers on shows. Max has no mother. He never had one."

Brooks had little involvement with the series after the first season, but Buck Henry served as story editor through 1967.

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