The sexual revolution may have arrived in 1966, but it will also be seen in the Masters' household with Libby, Virginia and Bill engaging in a controversial three-way marriage. While the teaser trailer hints at Libby and Virginia becoming intimate and even sharing a kiss, it looks like the arrangement may be rocked by an unexpected pregnancy.

TVGuide reports that the three-way marriage will be tested in the upcoming season three of "Masters Of Sex" when one of them gets knocked up. While the publication does not state who gets pregnant, it will definitely be a shock if Virginia Johnson lands up conceiving a child. However, at this point, it is anyone's guess since Libby could also land up getting pregnant.

While Masters is positively shocked at the news, the pregnancy is ill-timed. Bill and Virginia are not only perched at the peak of their career, they are also on the brink of publishing their ground-breaking book titled "Human Sexual Response." The publication hints that the threesome come up with an unusual solution, one that has many consequences.

Meanwhile, Entertainment Weekly reports that actress Emily Kinney of "The Walking Dead" fame joins the star cast in a recurring role. Kinney will play Nora, a woman in her 20s poised and brimming with intelligence. She was Bill and Libby's neighbor as a child. Kinney's Nora lands up becoming a sex surrogate in the next phase of Masters and Johnson's revolutionary research.

Actress Lizzy Chaplan, who plays lead Virginia Johnson, spoke to TVLine about new cast member Josh Charles who essays the role of a perfume tycoon.

She said, "He plays this millionaire perfume tycoon who starts working with Masters and Johnson at the Masters and Johnson Institute because he wants to unlock the secret of pheromones for his perfume business...For all of Masters' staid, buttoned-up uptightness, Dan Logan is all charm and charisma and so that is going to throw a wrench into all sorts of things."

Will Logan come between Virginia and Bill? Find out as season three premieres on Sunday, July 12 at 10 p.m. ET on Showtime.