According to Buck Henry, Talent Associates Producer Daniel Melnick came up with the basic idea for the show. Melnick told Mel Brooks and Henry that he wanted a character based on the two most popular film franchises at the time: the James Bond and The Pink Panther film franchises.
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In the closing credit sequence, one of the double doors fails to merge completely when it closes.
The opening credits are a sequence of Maxwell Smart going through various doors to reach CONTROL headquarters.
The closing credits are of Smart leaving CONTROL through the same doors, but he injures his nose on one door.