Unmoored by her mother's sudden death, Frances has never felt so diminished, or so old. She's painfully aware that strangers no longer look at her the same way - and that she's now, at thirty-two, older than the great aunt for whom she was named, who was killed in the seventies under mysterious circumstances involving an extramarital affair. Her husband, Ben, will do anything to help Frances regain her vivacity and sense of purpose. So when Frances suggests that they open their marriage, Ben complies. Over the next two years, they explore their sexualities and latent kinks; they navigate jealousy, betrayal, desire, and obsession; they defend their choices - and their new identities - to confused friends. They do all of this together, as a team. But when Ben finds himself falling in love with another woman, just as Frances realizes she's ready to settle down and have a baby, they are forced to confront the consequences of their experiment.