When deeply conservative English local Edith Swan and fellow residents begin to receive wicked letters full of unintentionally hilarious profanities, her rowdy, foul-mouthed, Irish migrant neighbor Rose Gooding is charged with the crime. The anonymous letters prompt a national uproar, and a trial ensues. However, as the town’s women—led by Police Officer Gladys Moss—begin to investigate the crime themselves, they suspect something is amiss and Rose may not be the culprit after all.