Eager to escape the heat of London in July, Terry Manstone goes on a hiking trip in Sussex - only to find herself lost, with darkness and a storm approaching. Hoping to make it to the next village, she sprains her ankle, and becomes a guest in a nearby house. Here she meets the handsome Dr. Blaise Farlong and his bitter, scheming wife Ruth. Terry never thought she'd fall in love with a married man; and when Ruth's machinations push her into Blaise's arms, their problems are only just beginning...