Showtime is concluding the fourth season of its sexually charged drama “Masters of Sex” on Sunday. Last week, sex researchers Dr. William “Bill” Masters and Virginia “Gini” Johnson pondered over their relationship and realized what they want from each other.

Here is everything you need to know about the upcoming episode of “Masters Of Sex”:

1. Bill And Virginia Are Getting Married

Bill (Michael Sheen) and Gini (Lizzy Caplan) will break the good news to everyone including Barton Scully (Beau Bridges), Bill’s ex-wife Libby (Caitlin Fitzgerald) and the rest of the people working at the clinic.

2. But Most People Don’t Support Their Decision

Unfortunately, except for Barton, most people don’t support the couple’s decision to tie the knot. Lester (Kevin Christy) tells the duo in the promo of the Season 4 finale that he hopes their marriage isn’t “soul-crushing, testicle-shrinking never ending abyss of misery” like his is with Jane (Heléne Yorke).

Next, Virginia’s mother tells her that marriage may not be such a good idea at her age. After three children and a failed marriage, does she really need to tie the knot with another man?

3. Dody Is Back

Perhaps the most interesting aspect of the Season 4 finale of “Masters Of Sex” is the fact that Bill former lover Dody (Kelli O’Hara) will be back. Will she stop his impending nuptials with Gini? We hope not!

4. Libby And Her Kids Move Halfway Across The Country

Libby has enrolled to study law. However, a professor inspires her to move halfway across the country to California and apply for classes in the University of California in Berkeley. She is really taking her career seriously.

Of course, this decision won’t sit well with Masters because she will be taking their kids along with her. Nevertheless, Libby will talk him into accepting her decision.

5. Art Rats Out Nancy

The last episode of “Masters Of Sex” saw Art (Jeremy Strong) learning that his wife Nancy (Betty Gilpin) didn’t abort their child because she wasn’t sure of the father. She knew Art was the father of her child. The reason she terminated her pregnancy was because she always wanted the option to leave her husband. Having a child removes that option.

Perhaps this is the reason why Art rats out Nancy to Bill and Gini. He informs them that she intends to start her own sex clinic in New York using their techniques and procedures.

“Masters Of Sex” Season 4 finale airs Sunday, Nov. 13 at 10 p.m. EST on Showtime.

Masters Of Sex How will Libby react to Bill marrying Virginia? Find out by catching “Masters Of Sex” Season 4, episode 10 on Sunday, Nov. 13 at 10 p.m. EST on Showtime. Photo: Showtime