Heavy snow is falling in Dartmoor and the shadowy guests in the local hotel decide to take part in a seance in order to amuse themselves. But the evening takes on a more sinister edge when the table-turning suggests that Clive Trevelyan, an eminent politician, is in danger. Meanwhile, at Sittaford House, Miss Marple discovers that poisoned Turkish Delight has been sent to Trevelyan. John Enderby, Trevelyan's loyal right hand man, is so concerned for his friend's safety that he wants to check on him. Unfortunately, Trevelyan is staying at the hotel - six miles away and, with snow drifts blocking the roads, someone will have to make the journey on foot...