Velvalee Dickinson was Japanese spy in the US during World War II. She was known as the 'Doll Woman' because she used her dolls business as an analogical code. Such a message was 'Doll in a hula skirt is in the hospital and doctors are woerking around the clock' which translates as 'Destroyer USN Honolulu is badly damaged and in Seattle undergoing around the clock repairs.'
She was finally caught when one of her contacts in Brazil moved and her messages were returned.
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