Former MMA fighter Aiden "Irish" O'Brien hasn't stepped into the ring since he accidentally took someone's life in the heat of rage. When his friend calls in a favor that sends him south to check on family, Irish figures he's got nothing to lose. His life is on the ropes. The least he can do is make sure the sexy redhead is safe.Kat MacGregor has forty-eight hours to settle the twenty thousand dollar debt her deadbeat ex-boyfriend owes a crime boss. If she doesn't, she'll pay for it-with her life. Kat's halfway out the door when a sexy new guy walks into the bar and insists he's there to help.Irish is forced to fight in the underground MMA circuit to win the money she needs. But he's been lying to Kat. About who he is, about knowing her sister, about why he comes home bruised every night. She's the best thing that's ever happened to him, but breaking her trust will cost him the most important fight of his life: the one for her heart.