Like his brothers, Luis Fuentes is a risk taker; whether he's scaling the Rocky Mountains or dreaming of a future as an astronaut, Luis is always looking for the next thrill. Nikki Cruz lives her life by certain rules - don't trust a boy who says "I love you", boys lie to get their own way and never date a boy from the south side of Fairfield. Then she meets Luis at his brother Alex's wedding and suddenly she's tempted to break all her rules. Getting Nikki to give him a chance is Luis's biggest challenge, until he finds himself targeted by the head of the gang that nearly destroyed his brothers' lives. Will Luis's feelings for Nikki be enough to stop him from entering a dark and violent world that could prove to be the ultimate risk? The final instalment in the steamy, romantic and thrilling Perfect Chemistry trilogy.