At the start of the book, a mother and her disabled son are killed when they eat poisoned chocolates, brought by her husband (Dr Meyer). This looks like an open and shut case, but the husband claims he didn't do it. The examining magistrate, Porfiry Petrovich, investigates and wants to make a thorough investigation before he comes to any conclusions.

Porfiry is a character taken from CRIME AND PUNISHMENT by Dostoevsky. In that book, it is his subtle examination of Raskolnikov, the main character in the book, which eventually leads to Raskolnikov's confession of murder. It is a interesting decision taken by R N Morris to re-use this character in this new book. Porfiry is a short fat man, with a haemorrhoid problem, who has rooms adjacent to his office, and is unmarried. As it is summer in St Petersburg, he has a particular problem with the smell from the nearby river, due to the sewage that is dumped in there, and which results in numerous flies in his office. Porfiry also has a new assistant to help him uncover the true murderer, Pavel Pavlovich Virginsky. As Porfiry explains his thinking to Pavel, to instruct him in just how detection should be done, we also find out something about how Porfiry's mind works and pick up some useful clues.

When they interrogate Dr Meyer, he claims that just after he bought the chocolates, an unknown man bumped into him, knocking the box out of his hand. He suggests that this unknown man might have substituted his chocolates for a box of poisoned ones and points the finger at Bezmygin, a musician that he suspects of having an affair with his wife. While interviewing Bezmygin, Porfiry and Pavel discover that the doctor had been sent an anonymous letter concerning his wife, which had resulted in strained relations between them. They search Dr Meyer's study, find the letter and confront him with it, as it appears to provide a motive for murder.

However, then a man is shot and the circumstances of this murder show parallels with that of Dr Meyer's wife. Colonel Setochkin is shot in his study, and when the servants enter to investigate, his visitor Vakhramev, who had been heard threatening to kill the Colonel, is found holding a gun. But Vakhramev protests that he didn't do it. He claims that he had left the room, heard the shot, come back in and picked up the gun. The window to the balcony was open. Could someone else have come in and shot the Colonel? Intriguingly, Vakhramev also claims that he had received an anonymous letter that had accused the Colonel of having a relationship with Vakhramev's daughter, prompting his visit. But the letter has mysteriously disappeared. Porfiry shows him the anonymous letter that Dr Meyer received and Vakhramev comments that the handwriting was very similar to that on the letter that he had received. Is there a connection and if so, what is it? Is the real murderer the writer of the letters? With some careful detective work, but not without further murders, eventually they find the culprit and the motive for the crimes and they confront the murderer, with tragic consequences.

This is a well-written and intriguing book. The setting of St Petersburg and its surroundings during the summer time, at the time (1868) when the Tsar was in power, provides an interesting backdrop to the main story, with good descriptions of the poverty and living conditions of much of the local population. The two leading characters, Porfiry, with his experience and doggedness and Pavel, with his naivety, and frustration with mundane but necessary tasks, work well as a combination. Through their discussions, and the emergence of clues, we are gently led through the detective process to discover the true identity of the perpetrator of the crimes in a very satisfying way. A thoroughly enjoyable book and I highly recommend it.