It is the day of the presentation, but as Masters explains his work his colleagues' reaction is not what he had expected. Dr. Hass considers a job at UCLA Hospital. Scully undergoes electroshock treatment but Margaret is worried about the risks.
With Virginia out of the team, Libby offers to help him prepare for a presentation of the study at the hospital. His research is incomplete but he will do anything to grab his fellow doctors' attention. Dr. DePaul and Virginia go to a medical convention. Virginia's husband returns only to find his child in the loving arms of Dr. Haas.moreless
Problems among the hospital's staff arise when they participate in a civil defense drill. A pregnancy is anounced while Masters and Virginia argue about maintaining the study's confidentiality. Haas is unemployed and believes it is Vivian's fault. Scully finds a source that could help her answer questions about her husband's sexuality.moreless
Lester and Jane must be convinced when Masters and Virginia decide to take their study outside an film it, which could mean crossing a dangerous line. Haas and Vivian0s plans for their weddding get complicated as he reveals sometging unknown. Libby keeps her secret while helping masters work on his relationship with his mother. Estabrooks discovers something.moreless
Masters and Virginia find an excellent way of keeping record of their work but they will need some extra help. Virginia returns to college but things prove not to be so easy. Dr. Haas and Langham discuss their married lives. Also, Scully's sexual impulses are put to the test by Margaret's discovery.moreless
Despite Virginia's concerns, she and Masters become participants in their study. Libby wants to resume her fertility treatments with Dr. Haas. Margaret Scully's husband discovers her infidelity. Haas continues to be torn between his feelings for Virginia and his relationship with Vivian.
Masters and Libby decide to go on holidays to Miami to recover from their loss, but Masters meets a couple that gets his attetion. Meanwhile, Virginia works with Jane to prove one of Freud's theories wrong. Langham finds a new connection with Margaret Scully from which he could benefit.
Attraction comes into play when Masters and Virginia decide to expand their study to couples. Masters starts feeling anxious about the upcoming birth of his baby while Virginia struggles with her son and their relationship. Also, Dr. Haas fears for his medical career after a date.
With location problems solved, Masters and Virginia start recruiting new participants for the study with a shocking surprise. Libby tries to play matchmaker and Virginia remembers her childhood as a result of her mother's visit.
As the study continues, new difficulties appear regarding its location. At the hospital Virginia meets a new female OB/GYN. Also, Dr. Ethan Haas gets a very special case and Libby finds it difficult to conceive.
Dr. Masters puts Virginia's job in jeopardy when he asks her to participate in a part of his study. As Virginia struggles both at home and at work, Masters is forced to move his study to another location. He soon discovers he needs Virginia's help.
Dr. William Masters starts a secret study of human sexuality. We also see him run his medical practice, at a midwestern teaching hospital in St. Louis, as an OB/GYN by day while he works on his project by night. A new secretary, Virginia Johnson, shows promising relevance to his studies.