Mary and Joe St. John are young, modern, and have an ideal marriage--almost. Their sex life isn't everything they think it should be. Proactive and determined, they embark on a quest to improve life in the bedroom by any means and at any cost--and they have allowed a documentary film crew to record their struggle. On the course of their journey, Mary and Joe seek counsel from three sources: a sex therapist who probes their motivations and insecurities through the new technique of "replacement therapy"; a urologist who addresses physical issues medically with innovations such as the "clitoral pump"; and tantric counselors who teach ancient sex techniques such as "sacred spot massage". Unwilling to let propriety or finances deter them, Mary & Joe delve into increasingly invasive and expensive therapies that strain their relationship to its limits. In the course of their quest, Mary and Joe learn more about themselves and their relationship than they bargained for, and they are led to a result they could not foresee.