Ide, Joe. IQ novel.

Thorndike Press large print mystery series.

Ten years ago, when Isaiah Quintabe was just a boy, his beloved brother was killed by an unknown assailant. The unsolved crime has gnawed at his gut and kept him up nights, boiling with anger and thoughts of revenge. The search for the killer sent him plunging into despair and nearly destroyed his life. Now, Isaiah has a flourishing career, a new dog, and a near-iconic status as a PI in his hometown of East Long Beach, but a chance encounter reopens a wound that never fully healed. He has to begin the hunt again - or lose his mind. A case takes him and his skeptical don't-call-me-a-sidekick partner, Dodson, to Vegas, where Chinese gangsers and a terrifying seven-foot loan shark are stalking a beautiful DJ and her deadbeat boyfriend. If Isaiah doesn't find the couple first, they'll be murdered. Awaiting the outcome is the love of IQ's life: fail, and he'll lose her. Isaiah's quest is fraught with treachery, menace, and startling twists, leading him to the mastermind behind his brother's death, Isaiah's own Moriarty. Rich with action, suspense, and ingenius surprises, Righteous confirms Joe Ide as one of crime fiction's most exciting new voices