Who said nothing ever happens in the French countryside? Picardie, 1964. On a deserted country road, three Moroccan nationals are shot dead with precision, a cold-blooded execution, one bullet each. To Inspector Lucas Rocco, it's a mystery. Why them and why here? A short time later, he happens upon two police officers who have been assaulted by an enraged motorist, one of them seriously. The unapologetic assailant, found to have an unregistered gun in his possession, claims to be the secretary of a high-profile and influential Parisian lawyer, Guy De Lancourt. The two cases seemingly have nothing in common. But on closer examination Rocco feels something isn't quite right. Just what lies beneath De Lancourt's carefully-cultivated public persona? And what secrets are hidden at Les Cypres, the heavily-guarded former mental asylum De Lancourt has made his home?