All episodes for series 4 of Masters of Sex

S4 E1 · Freefall

Masters is caught drunk-driving and Johnson works with Hugh Hefner.

S4 E2 · Inventory

Masters and Johnson focus on their expanding clinic.

S4 E3 · The Pleasure Protocol

Masters and Johnson adjust to new partners.

S4 E4 · Coats or Keys

Johnson, Masters, Libby, Betty, Lester and Keller wind up together at a swingers party.

S4 E5 · Outliners

Masters is forced to make a difficult admission.

S4 E6 · Family Only

Johnson tries to get her relationship with Bill back on track.

S4 E7 · In to Me You See

Masters intends to make Art his protege as he expands his research.

S4 E8 · Topeka

Masters and Johnson go on the road and pose as a couple at a competing clinic.

S4 E9 · Night and Day

Masters and Johnson must deal with the ramifications of their trip to Topeka.

S4 E10 · A Private Affair

As the practice disintegrates, Masters and Johnson make an important choice about their future.