From the Bookshelf of The Reading Challenge Group…

'Briefly the story is this: Picaud, a young man from the south of France was imprisoned in 1807, having been denounced as an English spy, shortly after he had become engaged to a young woman called Marguerite. The denunciation was inspired by a cafe owner, Mathieu Loupian, who was jealous of Picaud's relationship with Marguerite.

Picaud eventually moved to a form of house-arrest in Piedmont and shut up in the castle Fenestrelle, where he acted as a servant to a rich Italian cleric. When the man died, abandoned by his family, he left his money to Picaud, whom he had come to treat as a son, also informing him of the whereabouts of a hidden treasure. With the fall of Napoleon in 1814, Picaud, now called Joseph Lucher, was released; in the following year, after collecting the hidden treasure, he returned to Paris.

Here he discovered that Marguerite had married Loupian. Disguising himself, and offering a valuable diamond to Allut, the one man in the group who had been unwilling to collaborate in the denunciation, he learned the identity of his enemies. He then set about eliminating them, stabbing the first with a dagger on which were printed the words: 'Number One', and burning down Loupian's cafe. He managed to find employment in Loupian's house, disguised as a servant called Prosper. However, while this was going on, Allut had fallen out with the merchant to whom he had resold the diamond, had murdered him and had been imprisoned. On coming out of jail, he started to blackmail Picaud. Picaud poisoned another of the conspirators, lured Loupian's son into crime and his daughter into prostitution, then finally stabbed Loupian himself. But he quarrelled with Allut over the blackmail payments and Allut killed him, confessing the whole story on his deathbed in 1828.'

'...not many children's books, even in our own time, that involve (view spoiler)[a female serial poisoner, two cases of infanticide, a stabbing and three suicides; an extended scene of torture and execution; drug-induced sexual fantasies, illegitimacy, transvestism and lesbianism; (hide spoiler)] a display of the author's classical learning, and his knowledge of modern European history, the customs and diet of Italians, the effects of hashish, and so on; the length, in any case, would immediately disqualify it from inclusion in any modern series of books for children.'