With her son Edward (Tom Hiddleston) about to embark on a volunteer trip to Africa, doting mother Patricia (Kate Fahy) wants to give him a good send-off, and gathers her family together for a getaway to a holiday home on idyllic Tresco, one of the Isles of Scilly       Edward’s father’s attendance is eagerly anticipated, though sister Cynthia (Lydia Leonard) appears to be there unde