It's late August in Shetland, and indomitable sailor Cass Lynch finds herself looking after an old lady who's recovering from a broken leg. It should be peaceful in Tamar's isolated cottage, but there's been a break-in while she was in hospital - someone apparently searching for papers. Cass suspects Tamar knows more than she's saying about her family's link to the local Laird - and when her family start to gather round, secrets begin to be exposed. Then the body of a dark-clad man is found in a cove just around the corner. It looks like an accidental fall, but soon the police are involved.