During a hiking holiday at the resort of Wilvercombe on the South West coast of England, the detective novelist Harriet Vane discovers the body of a man lying on an isolated rock on the shore; his throat has been cut. Harriet takes photographs and notes that death must have been very recent as the man's blood is still liquid. There are no footprints in the sand other than hers and those of the victim. Unfortunately, the corpse is washed away by the rising tide before she can summon help. Alerted to the discovery by a friend, Lord Peter Wimsey arrives, and he and Harriet start their investigations. The victim is identified as Paul Alexis, a young man of Russian extraction, employed by the local hotel as a professional dancing partner. The police tend to the view that Alexis's death was suicide and that he had cut his own throat. Wimsey and Harriet discover that in the period leading up to his death Alexis, an avid reader of Ruritanian romances, had believed himself to be a descendant of Tsar Nicholas I of Russia. A series of coded letters received from an unknown source convinced him that he was being called to return to Russia to take his place as the new rightful Tsar. Alexis had recently been engaged to a rich widow in her fifties, Mrs Weldon. Her son, Henry Weldon, ten years older than his mother's lover and by all appearances a simple and brutish man, is appalled at the prospect of his mother's remarriage to a gigolo, and at his potential loss of inheritance. He travels to Wilvercombe to monitor the investigation while ostensibly comforting his mother after her loss. Weldon appears to be a likely murder suspect, but he has an unshakeable alibi for the time of Alexis's death – as do a large number of other possible suspects. Alexis's death, staged to look like suicide, is gradually revealed to be the result of an ingenious murder plot that played upon Alexis's fantasies. He had been lured to the rock by his anonymous correspondent who urged him to be ready to meet a 'Rider from the Sea', a rider who it was said would be carrying instructions for his onward journey to Warsaw. Once at the rock, Alexis met his death at the hand of the murderer who had ridden his horse along the beach through the incoming tide to avoid leaving tracks. Wimsey and Harriet ultimately realise that Weldon is not the simple character he has been presenting, but a criminal who has been living under two different identities. Weldon was himself the rider, and had been provided with his alibi by two co-conspirators, a friend and his wife. Although his alibi was secure for the believed time of death, the investigators discover that Alexis had died far earlier than had been thought. The still-liquid and unclotted blood noted by Harriet when she found the body had been the result of Alexis's haemophilia. Weldon and his co-conspirators are undone by their unsuccessful attempts to reshuffle their alibis to match the new information about the time of death. Even as Wimsey and Harriet solve the case, Mrs Weldon has already moved on to another gigolo at the hotel, a sympathetic French dancer named Antoine.
Title
The novel's title appears in William Cowper's translation of Book II of Homer'sIliad: "The vulture's maw / Shall have his carcase, and the dogs his bones".
Characters
Lord Peter Wimsey – protagonist, an aristocratic amateur detective
Miss Harriet Vane – protagonist, a detective novelist with whom Wimsey is in love
Paul Alexis – a professional dancing partner at a hotel
Mrs Weldon – an elderly wealthy widow, engaged to Alexis
Henry Weldon – only son of Mrs Weldon
Haviland Martin – a suspicious camper who proves hard to trace
Bright – an itinerant hairdresser with a cloudy past, who gives evidence to suggest that Alexis's death was suicide
Inspector Umpelty – local policeman in charge of the investigation
Chapter heads
All the chapter heads feature quotes from the works of dramatist and poet Thomas Lovell Beddoes.
Criticism
In their overview A Catalogue of Crime Barzun & Taylor noted that the book was "A great achievement, despite some critics' carping. The people, the motive, the cipher, and the detection are all topnotch. Here, too, is the first use of hemophilia as a misleading fact. And surely the son, the mother, and her self-deluded gigolo are definitive types".