The First Fingerprint introduces a policeman as polished as he is brutal, as charming as he is streetwise and as deceptively noble as he is coarse. Michel de Palma, called "the Baron" by his colleagues, knows the dark underside of the city of Marseille as do none of his rivals. But his enemies are everywhere: in the crime-infested sinks of the suburbs; in the sleek and squalid bars of the old quarter; even in the police ranks themselves.

When Marseille is thrown into turmoil by a series of savage murders, each signed with a print of a three-fingered hand, the Baron is ordered to drop his present investigation into the puzzling death of historian Christine Autran. But the Baron ignores his instructions, for unbeknown to his colleagues he has discovered a bizarre connection between the two cases. Autran was researching Le Guen's Cave, an underwater cavern containing some of the earliest engravings known to man - including a crude drawing of a three-fingered hand.

De Palma heads to the university in Aix-en-Provence to investigate further, but the clique of pre-history professors he encounters are as hard to unravel as the meaning of the cave-drawing itself. As he gets closer to the truth, the group of academics closes ranks. Deliberately and alone, de Palma begins pursuing a mystery that dates back to the Ice Age.