Scalped (Book 5) - Jason Aaron

The search for his mother’s killer has been the anchor keeping undercover FBI agent Dashiell Bad Horse from being swept away in the chaos engulfing the Prairie Rose Indian Reservation. Now that he has at last discovered the truth, the way is finally clear for Dash to fulfill the promises he made to both his employer and his mother’s spirit. But the man who murdered Gina Bad Horse is still at large, and the FBI’s target—Chief Lincoln Red Crow—is about to complicate things by burning down his own criminal network. After years of violence and exploitation, a new rez is poised to rise from the ashes of the old—and no one knows who will be left alive to see it.