Ancient Athens, 421 B.C.
A peace treaty has just been signed with Sparta, and the Peloponnesian War has subsided.
The twelve-year-old aristocrat Diogenes, who works as an assistant in the city library, hears a noise in the area where the precious books are kept.
He runs to see what is happening and sees a shadow running away holding the Homeric epics...
When he recounts the events to his friends, Laertes and Lysimachus, they decide to take action and solve the mystery, defending their homeland and democracy!