Healy James and Fisher Hart share a deep secret, but they don't know what it is. While Healy is tormented by compulsions he doesn't understand, Fisher studies the science of love, and avoids Healy, who triggers feelings she can't explain. When Healy suspects the answers to their mystery are buried on a suspected killer's property, his curiosity turns reckless, and Fisher must choose between a life in hiding and a frightening truth.