Warning: for reasons explained below, this review may contain spoilers for another book by the Coles, Dr Tancred Begins.
Dr Ben Tancred is a private investigator who appears in two books by G. D. H. and M. Cole. Unusually, although both publlshed within a year of each other, they are set about twenty-five years apart. What is more, several of the characters in the earlier book also appear in this one, which means that they should be read in chronological order if possible. Unfortunately, they are both quite scarce books, particularly the first of the two, and I've only read this, the second. (It was reprinted some years ago as part of the Crime Club series "The Disappearing Detectives", but I don't think this had a very large print run.)
Dr Tancred is approached by an old acquaintance, Sarah Pendexter, in connection with the recent death of Lord St. Blaizey. She believes very strongly that it was murder (which view she shares with the doctor who examined the body) and that it was committed by her nephew, Rupert. However, this view appears to be mainly based on her claim that she saw the murder committed in a vision (she is a religious fanatic, and many people consider her insane). However, Tancred thinks that her other claim, to have seen Rupert riding on a horse in the vicinity of the crime (which was carried out by knocking the old man off his horse, in the woods near his residence), to be more credible, and eventually he decides to agree to investigate the case.
After consulting Superintendent Wilson (who was involved in the previous case, but plays only a small part in this one), Tancred goes down to the area where the victim lived (in Cornwall, near the river Fowey) and starts to look into the case. Another person whom he had met before is Rupert's sister Helen, who is now married to the victim's son, and hence has become Lady St Blaizey as a result of her father-in-law's death. Could she be involved in the murder? We have learned in the first chapter that she was previously tried for the murder of her stepfather (the story of this is told in the earlier book), and Ben was the main person responsible for her acquittal. He thought that he knew who really was the killer on the earlier occasion, but was unable to prove it, and that person is the principal suspect now. However, it takes a good deal of investigation to bring the case to a climax, with other issues involving a possibly forged will and a second murder.
It should be added that the book is set in a real area, with only slight changes to some place names (the reasons for which don't entirely make sense) and I was interested to note, by comparing the map provided with a modern road-map, that the area covered would today have to include the Eden Project! ( )