Based on a stranger than fiction true story, Wicked Little Letters follows two neighbours: deeply conservative local Edith Swan (Olivia Colman) and rowdy Irish migrant Rose Gooding (Jessie Buckley).

Their 1920s English seaside town bears witness to a farcical and occasionally sinister scandal when Edith, and fellow residents of Littlehampton, begin to receive wicked letters full of unintentionally hilarious profanities. The anonymous letters prompt a national uproar, and a trial ensues, and Rose (Buckley) is accused of the crime. However, as the town’s women – led by Police Officer Gladys Moss (Anjana Vasan) – begin to investigate the crime themselves, they suspect that something is amiss, and Rose may not be the culprit after all.