We kick off at a seedy bar called the Poivrière, where three people are found dead. The police, led by the weary veteran Gevrol, quickly arrest a man covered in blood who calls himself May. Case closed, right? Enter our hero, the young and eager police agent Monsieur Lecoq. While Gevrol sees a cut-and-dried affair, Lecoq spots inconsistencies. Why was one victim shot with a fancy, expensive pistol in a dive bar? Why does 'May' switch his story and seem to be acting a part?

The Story

Lecoq convinces his skeptical supervisor, Papa Tabaret (an amateur detective genius), that there's more to the case. They focus on the prisoner, who is a brilliant actor and escape artist. The bulk of the book becomes a tense cat-and-mouse game. Lecoq tails the suspect after a daring escape, using every trick of surveillance he can think of. The suspect, in turn, leads him on a dizzying chase through Paris, constantly changing disguises and identities. Just when Lecoq thinks he's cornered his man at a fancy aristocratic mansion, the story throws a massive curveball that questions everything he's discovered. The first volume ends not with a tidy solution, but with Lecoq facing a wall of high-society silence and a mystery that has grown far bigger than a bar fight.

Why You Should Read It

This isn't just a whodunit; it's a how-does-a-detective-think manual. Gaboriau shows us the grind of police work—the stakeouts, the dead ends, the meticulous note-taking. Lecoq isn't a superhero; he makes mistakes, gets outsmarted, and runs on caffeine and sheer stubbornness. His passion is contagious. You're rooting for him because he's using his brain against a system that prefers easy answers. The real thrill is watching logic and observation clash with deception and privilege.

Final Verdict

Perfect for mystery lovers who enjoy the journey as much as the destination. If you like the methodical parts of Sherlock Holmes or the historical atmosphere of The Alienist, you'll feel right at home. Be prepared for a cliffhanger—this is only the first half of Lecoq's debut case. It's a fascinating look at the birth of the modern detective novel, starring a character who had to earn his genius badge the hard way.