On a return trip from Germany, Monkand Natalie stop over in Paris. They visit the catacombs, a vast, undergroundcavern in the center of the city lined with millions of human bones. Monk picksup a skull and announces that the person was murdered. Most of the bodies camefrom a battlefield, but Monk believes the wound that killed this man came froma modern weapon made in the last few years. He thinks someone hid a recentmurder victim among the ancient bones. As Monk starts to investigate the crime,he uncovers another murder that involves a society of "dumpster divers," peoplewho live commerce-free off the waste of society. It might just be the laststraw in Monk's visit to Paris.