The Emerald Lie - Ken Bruen

From the "Godfather of the modern Irish crime novel" (Irish Independent), The Emerald Lie introduces a villain of the most unusual type: an Eton and Cambridge graduate who becomes murderous over split infinitives, improper punctuation, and any other sign of bad grammar. Ken Bruen's irascible protagonist, ex-cop Jack Taylor, is meanwhile approached by a grieving father with a pocketful of cash on offer if Jack will help exact revenge on those responsible for his daughter's brutal rape and murder. Jack agrees to get a read on the likely perpetrators but is soon derailed by the appearance of Emily (also known as Em, Emerald), a chameleon-like young woman who is by turns passionate, clever, and utterly homicidal. She is ready to use any sort of coercion to get Jack to conspire with her against the serial killer the Garda have nicknamed "the Grammarian," but her most destructive obsession just might be Jack himself.