Folkestone, 1921. Newly-wed Maude Brent couldn't be happier. When her much-loved elderly housekeeper Aunt Biddy starts to grow forgetful, her husband Lionel suggests that Maude hire a companion - and he knows just the girl. Initially reluctant, Maude trials the young Alice, and soon it's as if she'd always been part of the family. But when Lionel takes Maude on holiday to Hastings, tragedy strikes and he disappears. A body is washed up on the seafront and a distraught Maude fears the worst - but it's not Lionel, and when a ransom demand is sent to her, she is reassured to know he is alive. However Maude soon discovers she's at the centre of a twisted plot to do her wrong...