Hailey is an up-and-coming biologist, and sexual evolution is her passion. Natural selection works best, she believes, when a woman has lots of options. Between her studies and her job as a bike messenger, Hailey hasn't had time to do much more than be a voyeur watching the nocturnal habits of her own species in the city's nightclubs. Everything changes when she meets Noah and Cade, two very sexy men who will overturn her views on human mating games. But Hailey knows a lot more about animal passion than they realise and, before they know it, she's the one doing the hunting - with Cade, Noah, and a rugged big cat handler named Rick as her prey.