This 1931 mystery by the prolific author, Joseph Smith Fletcher, is the first in the series featuring Ronald Camberwell---who at this stage we cannot properly call "a detective", whatever he might do later, but rather fills the role of narrator-sidekick. Having come into his inadequate inheritance, Ronald is fortunate to land a cushy job as secretary-companion to the elderly Christopher Nicholas, who lives at his estate, Wrides Park, with his only relative, a niece. One day while Mr Nicholas is out, a rough, bullying man who calls himself Dengo pushes his way into the house, rudely making himself at home. When Ronald breaks the news of Dengo's arrival to his employer, he sees that it is a shocking blow to him; nevertheless, Nicholas sees his unwanted visitor, and later the two men are seen walking together through the grounds---where Dengo is later found dead, stabbed through the back with Mr Nicholas's sword-stick... Murder At Wrides Park is an engaging if not exactly exciting mystery, one content to build its plot upon dogged investigative work rather than brilliant deduction. But though it is a procedural, it is not a police procedural: the main investigator is a former Scotland Yard inspector turned private investigator called Chaney. The revelation that Dengo had been blackmailing Nicholas for years over a secret in his past is enough for the police - particularly in conjunction with their suspect's rash admission that he has 'blacked-out' the night of the murder, due to alcohol consumed - but those who know Nicholas well can't believe it. When Nicholas is arrested, his solicitor hires Chaney, who in turn allows Ronald to tag along as he hunts down alternative suspects. The day he was killed, Dengo had received fifteen hundred pounds from Nicholas, but this money was not found on the body. Chaney starts at the very beginning, trying to determine Dengo's real identity, before pursuing the bigger questions: who knew he was going to Wrides Park? - who knew he might have money on him? - and who, even aside from the money, might have wanted him dead?

Chaney went off to the West End, to seek out his possible informants; I, to Wrides, pondering all the way on the things I had heard and seen. Once more the old question came up---who was Ogden and what was the secret between him and Mr Nicholas which Mr Nicholas was so obstinately resolved to keep a secret foe ever? Should we solve it?---and would the solution save him? I saw the obviousness of the police theory---Nicholas, desperate at the continued urgings of blackmail, and under the influence of the drink he had taken to drown his woes, had turned on and killed his blackmailer. There it was in plain fact---and it was the sort of straightforward theory that would appeal to a jury. No intricacies, no twists and turnings; just the sort of case the average juryman likes, requiring no mental effort...