Mrs. Pollifax and the Whirling Dervish(1990)

Dorothy Gilman

All Mrs. Pollifax has to do is to masquerade as the aunt of an inept CIA representative while he confirms the identities of seven undercover agents in Morocco—and keep him from making an unpleasant ass of himself. Immediately, things go horribly wrong. The first informant is murdered minutes after Mrs. Pollifax and her companion identify him in his brassware stall in Fez. Worse, she senses that her colleague is not who—or what—he says he is.
With no one to bail her out, Mrs. Pollifax determines to outfox the enemy and check out the remaining informants on her own. Only Mrs. Pollifax would expose herself to the dangers of being an American and a woman alone in Morocco. And only she would forge ahead, knowing as she does that one of the original informants has been replaced by a deadly imposter...