Already renewed for a second season, Showtime's period drama 'Masters of Sex' has quickly emerged as one of the best new dramas of 2013, thanks in large part to the revelatory performances of series leads Lizzy Caplan and Michael Sheen. Less than halfway through the inaugural season however, should we be worried about Showtime's infamous tendency to stretch series beyond their limits? A new interview about the show's future already has us clutching the sheets in anticipation.

Given the universally-agreed upon over-extension of 'Dexter,' and the general consensus that 'Homeland' has been meddled with so as not to kill off its most bankable stars, it seems 'Masters of Sex' may yet be the next target of story-padding for the sake of longevity. Speaking to The Hollywood Reporter, showrunner Michelle Ashford admitted that the true life story of William Masters and Virginia Johnson amounts to approximately four seasons worth of content, though Showtime intends to space out the major mile markers of the series:

Asked about the most difficult decision in writing a second season of 'Masters of Sex,' Ashford conceded:

How far forward in time to go. If you look at the story from beginning to end, it has some very definite milestones in it. If we just went on the big milestones, we would basically have a four-season show. I think that in success, for business reasons, they want something longer than that, and so now we’ve had to think about how we would divide up the story if we make it longer than four seasons.

On the plus side, Ashford confirmed that the spine of 'Masters of Sex' would keep to truths present within Thomas Maier's original novel 'Masters of Sex: The Life and Times of William Masters and Virginia Johnson,' though the book's own gaps in storytelling enable the Showtime drama to flesh out characters in more interesting ways. Moreover, it's worth noting is that only historical details of Masters, Johnson, and Masters' wife Libby have been legally vetted for use on the show, making the peripheral characters fictional amalgams of several real-life individuals, embellished for storytelling's sake with themes of the time.

It's too early to say with any certainty if Showtime will learn from criticisms of either 'Homeland' or 'Dexter' to allow 'Masters of Sex' to unfold along its natural lifespan, though the first season remains increasingly promising that Ashford has a handle on the characters and material

In the meantime, check out a preview of 'Masters of Sex' next episode "Brave New World" below, and tell us in the comments how you think the Showtime drama should progress in future seasons!