the holidays have begun. In a seaside caravan resort, Isabel and her sister Meg build sandcastles with the children, navigate deckchair politics, explore the pier's delights, gorge ice cream in the sun. But their half-sister Mildred has returned to a nearby coastal cottage where her husband - the mysterious Uncle Paul - was arrested for his first wife's attempted murder: and family skeletons emerge.
Now, on his release from prison, is he returning for revenge, seeking who betrayed him? Or are all three women letting their nerves get the better of them? Though who really is Meg's new lover? And whose are those footsteps ...?