Here's a plot summary, courtesy of Wikipedia (I've cut out the bit about the ending, so no spoilers):
The novel interweaves two apparently disparate storylines: the first being an ancient Greek novel published in Athens just after the Peloponnesian War and the second contained within a modern-day scholar's notes on his translation. In the ancient novel (which is itself called The Athenian Murders) a young ephebe named Tramachus is discovered on the slopes of Mount Lycabettus, apparently attacked by wolves. His tutor at the Academy, Diagoras, enlists the help of a "Decipherer of Enigmas" (a detective named Heracles Pontor) to learn more about Tramachus's death. As Diagoras and Heracles investigate, more youths from the Academy are discovered brutally murdered. Their investigation takes them all over Athens, from mystery cult worship services to a symposium hosted by Plato
Meanwhile, the translator (who is never named) provides frequent commentary on the work, especially as it appears to him to be an example of a (fictional) ancient literary device called eidesis. "Eidesis" is supposedly the practice of repeating words or phrases so as to evoke a particular image or idea in the reader's mind, as it were a kind of literary steganography. As the translator works on the novel, he soon deduces that the "eidetic" secret concealed within the novel is The Twelve Labors of Heracles, one labor for each of the twelve chapters of the novel. The translator becomes obsessed with the imagery, going so far as to see himself depicted within the ancient work.
Partway through the novel, the translator is kidnapped and forced to continue the translation in a cell...
It sounds somewhat intriguing, and was the only Greek-set novel I had on hand for my trip, although I will see if I can find any others while I'm over here (in English). Have you read Somoza's novel? Any other Greek crime fiction? Do you have some recommendations?