Sir Abercrombie Lewker, the actor-manager detective, is among the people Bertrand Awdrey invites to spend a weekend at his newly renovated farm-house in North Wales. He spices his invitation with the promise of climbing on his private crags to which he has given traditional names such as Fat Man's Agony and Suicide Wall. Awdrey had been forced to resign from the Foothold Club some years before under suspicion of forgery, but most of his guests are still members.

There is an uncomfortable atmosphere the first evening at Plas Cwm Pennant. It is clear that no one likes Awdrey and there is active rivalry between an attractive widow and the daughter of one of the climbers for the attention of the youngest man present. The next morning the party attempts the private crags with fatal results. Sir Abercrombie suspects foul play and calls in the police, but he investigates on his own account as well.