There are plenty of mysteries set in the 1920s and solved by women, of which Agatha Christie's Miss Marple is perhaps the most famous, but I've decided to focus on the humorous ones to celebrate a new addition to the field.
Come Hell or Highball is the first of what promises to be a new series by Maia Chance. Lola Woodby, New York society matron, is none too aggrieved when her miscreant husband dies, but it turns out his debts were enormous, and she's going to have to figure out how to get an income. When one of the deceased's mistresses offers Lola a great deal of money to get back an incriminating roll of film, the chase is on. Accompanied almost everywhere by her cook, Berta, and her Pomeranian, Cedric, Lola dances and drinks her way past bootleggers, starlets, and society high and low to get paid and establish a detective agency.
Of course, the current leading author of fun mysteries set in the 20s is the prolific Kerry Greenwood. Her character-based Phryne Fisher mysteries take place in Australia, where likeable Phryne has a gay old time solving mysteries and plucking her friends out of jams along with dancing, flying, and amorous adventures. These books have also been made into a television series: Miss Fisher's Murder Mysteries.
Close behind Kerry Greenwood is Carola Dunn, whose Daisy Dalrymple mysteries take place in England. The Honorable Daisy has scandalized Society by becoming a reporter in these witty cozies. She often has to call in Scotland Yard (people do happen to notice when the famous get murdered) and the handsome Alec Fletcher is always happy to oblige.
Rounding out this edition of female sleuths is the witty Dandy Gilver series by Catriona McPherson. Money is tight even among the gentry in post-WWI Scotland, so Dandy Gilver contributes to the family finances (those boarding school fees for her children aren't going to pay themselves) by looking into things for her friends and other members of Society. Atmospheric and intricately plotted, these mysteries are good fun.
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