Noted obstetrician Dr. William Masters (Michael Sheen) teams up with divorced mother Virginia Johnson (Lizzy Caplan) to conduct pioneering research that unleashes the sexual revolution.

When he’s forced to relocate his study to a St. Louis brothel, Masters (Michael Sheen) has no choice but to rehire Johnson (Lizzy Caplan) in order to make things work.

As Johnson (Lizzy Caplan) bristles at the hiring of a new female doctor, Masters (Michael Sheen) worries that conducting their study in a brothel is jeopardizing the results. Haas (Nicholas D’Agosto) fights to be allowed to deliver quadruplets.

Painful memories of his childhood cause Masters (Michael Sheen) to question his own his ability to be a good father. Johnson (Lizzy Caplan) is surprised by the arrival of her ex-husband.

As Masters (Michael Sheen) is haunted by memories of his childhood traumas, Haas (Nicholas D’Agosto) looks to advance his career by dating Scully’s (Beau Bridges) teenage daughter.

As Masters (Michael Sheen) and Libby (Caitlin Fitzgerald) struggle with the fallout from her miscarriage, Johnson (Lizzy Caplan) proposes a study that challenges Freud’s theories of female sexual response. An unsatisfying sex life at home leads Margaret Scully (Allison Janney) to volunteer for the study.