Showtime's provocative sex drama 'Masters of Sex' has been canceled

"Masters of Sex" won't be back for a fifth season. Showtime has decided not to renew the show after four seasons.

Sources with knowledge of the decision told Variety that the producers had told the story they wanted to tell. That means its November 13 episode was the show's series finale.

"Masters of Sex" starred Michael Sheen and Lizzy Caplan as pioneers of the science of human sexuality, William Masters and Virginia Johnson, whose research is credited with setting off the sexual revolution.

The drama and its leads had been nominated for numerous Primetime Emmys, which led to one win for guest actress Allison Janney.

On the ratings end, the racy drama started 0ut strong for Showtime with an average 1.1 million live viewers. But over the following seasons, interest diminished. Its fourth season averaged just 453,000 viewers.