This series has gotten better with each book. In The Marathon Conspiracy Nico and Diotima investigate the murder of one girl and the disappearance of another, events which are apparently related to the death, 30 years earlier, of the tyrant Hippias. It’s all rather complicated and confused, with red herrings strewn liberally on the trail, but in the end Nico reveals all.
The author does a terrific job of staying close to historical accuracy and conveying some sense of life in Athens, while still keeping things light by using modern language, slang, and mild sarcasm and irony. In all, this was a pleasure to read.