Danny Riccuci thinks divorce is hereditary. After all, his family has been the poster child for failed marriages. The only exception is his sister, Maria, and she's married to the church. Danny's so sure he carries this divorce gene that he's never bothered to challenge the family curse. Rachel Levin's a teacher of human relationships. She knows all the scientific reasons for mutual attraction. She know the basis of the human needs that drive people into relationships. She knows the statistics of almost every aspect of her field. In fact, Rachel knows everything about human relationships--except what it's actually like to be in one. Together, Danny and Rachel learn there's a lot more to love than what's in a textbook and that, sometimes, genetics are highly over-rated.