Fiery Rose Gooding has little in common with the pious Edith Swan aside from them being neighbours in the seaside town of Littlehampton in the 1920s. But one day, Edith and others in the town start receiving scandalous letters written with foul language as eccentric as it is obscene, and the finger of suspicion immediately falls on Rose. As Rose stands to lose her freedom and the custody of her daughter, and outrageous letters continue to blight the town, police officer Gladys Moss begins to suspect something is amiss. Together with a group of resourceful women, Gladys endeavours to solve the mystery, liberate Rose, and catch the real culprit…