"The Nude Bomb" (1980)?
https://www.imdb.com/title/tt0081249/
From IMDb:
"An unknown terrorist has developed a new type of bomb that will destroy clothing, but leave people unharmed. Agent Maxwell Smart (this time without 99 or Hymie) is taken out of retirement and sent back into the field to track down who this madman is and put a stop to his plans."
99, played by Barbara Feldon in the original series, is not in this movie.
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