Riding the Night — Jaci Burton

AJ and Pax are undercover operatives for a government agency of bad-boy bikers known as the Wild Riders. While AJ is visiting Teresa, a high school sweetheart, a fight erupts in her bar between two biker gangs. One man is left dead and Teresa's brother is wrongly accused of murder. With no proof and Teresa as the only eyewitness, AJ, Pax, and Teresa point their Harleys toward the annual bike rally in South Dakota in hot pursuit of the real killer, and Teresa discovers a passion that brings both men to their knees.