Would it be too on the nose (or on something else) to say that Showtime’s Masters of Sex has reached the plateau stage? Most rookie series tend to fumble with quality like an adolescent with a bra strap. But the beguiling Masters has been both thrilling and remarkably consistent: From the very first episodes, the show has had a rhythm and quiet confidence that belied its years. It’s not noisy and it’s not particularly rough; unlike other prestige hours it doesn’t screw with our heads or play games with our hearts. Occasionally it’s downright abstemious: Last night’s penultimate episode was the first in weeks without a bang, and, because of that, there weren’t even any memorable whimpers. And yet, even dressed, the show’s many pleasures couldn’t be denied. Masters is the rare young series that knows what it wants and exactly how to achieve it.

Sorry. Let’s leave the bad puns in the opening, just as the show does. (Quick sidebar: I find Masters of Sex‘s panting, pun-heavy credits truly awful, a close runner-up to Homeland‘s interminable jazz-labyrinth. I just don’t understand why a sly and subtle series about grown-up emotions would introduce itself with a dopey montage that’s arguably less mature than a Blink-182 album cover.) The point being, I’ve fallen hard for Masters over the past few weeks. It goes without saying that the show’s nimble exploration of gender and power sets it apart from a macho cable landscape riddled with bullet holes and splashed with blood. But like the determined Dr. DePaul, Masters is no token. It has proven to be exceptional for what it is, not what it isn’t. Under the sure hand of showrunner Michelle Ashford, there’s a delicacy to the storytelling that strikes me as utterly unique, something unhurried and resolutely modest — not in its ambition but in its demeanor. Relationships simmer slowly, characters are treated gently and with great respect. The Eisenhower-era teaching hospital at Washington University has just as many affairs and conveniently metaphorical medical diagnoses as present-day Seattle Grace. Yet the desire lines between the personalities — historical and otherwise — are drawn so carefully and then looped around one another with such skill that we’re drawn in close without ever noticing the knots. Despite the title (and those cheesy credits), the show is intimate, not physical.

“Phallic Victories” lacked the explosiveness of last week’s bomb scare and was also, sadly, missing one of my favorite story lines, the slow, Sirkian tragedy of the Scullys. (Allison Janney, as Margaret, is giving one of my very favorite performances of the year. Beau Bridges, as the closeted Barton, hasn’t had a role this good since he was a Baker Boy. Instead, it focused on the blast radius of Bill and Virginia’s detonated relationship, as the former allowed his wife to moonlight as his assistant and the latter found a different grim mentor to nudge into the light. It’s a good sign when a show can so effortlessly shuffle the deck, pairing off characters like participants in a sex study and getting workable results. I only wish Ashford and episode writer (and Party of Five co-creator) Amy Lippman had adhered to a more rigorous scientific standard. If the point of the hour was to remove Masters and Johnson from each other’s orbit, then it was repeatedly undercut by the mocking presence of Ghost Virginia, who passed the time haunting the margins of Bill’s office and scolding him for the shortcuts he was taking. In fact, the repeated leaning on this trope was a shortcut of its own. That Masters’s bullheaded, dinner-ignoring focus is nothing without his more pleasant partner was already obvious. She’s able to parry; he merely thrusts.

Even so, it was a small price to pay if the reward was having Real Virginia’s seat filled, if only temporarily, by the luminous Caitlin FitzGerald. The actress has been revelatory as Libby Masters, taking a part that could easily be a dope or a doormat and making her a fully realized person. In lesser hands, Libby’s otherworldly patience with her ice floe of a husband would seem incomprehensible. But FitzGerald takes a sheltered, sensitive woman and shows us both the lock and the key. I loved the moment when she came across Virginia’s file — the literal paper trail of her husband’s infidelity! — and treated it like a fairy tale. “Did they fall in love?” she asks Bill from opposing beds, as if there could be no other reason for people to fuck 23 times, as if emotions, like orgasms in cheap paperbacks, always happen simultaneously. Thus far the most important revelation of Masters’s study is the idea that shock is generally a choice, a socially acceptable way to protect ourselves from the truths we already know but don’t want to admit to others. (I thought of this the other week when Bill’s mother, the fabulous Ann Dowd, suddenly dropped her mask and spoke to her son as a woman, not a caricature.) But surprise, real surprise — such as when Margaret, prodded by a prostitute, suddenly realized the truth about Barton, or last night when, after a fit of insomnia, Bill suddenly saw his wife as the complicated, sexual being she is, not the childish abstract he prefers her to be — can cut more sharply than any scalpel.

Helpful as it was to have Libby answering phones and keeping Jane company — and all the kudos to the delightful Heléne York; the show has improved as her screen time has increased — it did little to address Bill’s essential flaw: He can compile all the data in the world but has no idea how to make the world care. The headline here was Bill’s sudden willingness to sex up his study: fudging some findings on dick size in order to flatter his audience into paying attention. (As if 30 minutes on the minutiae of boning could ever be as dull as diverticulitis!) But I was more interested in the parallels to Dr. DePaul’s predicament. Julianne Nicholson has brilliantly communicated the relentless focus and drive of another medical professional; in everything from acumen to (lack of) personality, she’s every bit Bill Masters’s equal. Yet her struggles have illustrated an even more insidious double standard. It’s not just that a female doctor has to work twice as hard to be recognized in 1950s America, it’s that 1950s America is constructed expressly to keep it that way. Despite being a bullying social disaster, Bill Masters is cheered and supported at every turn. In a man, chilliness and professional remove is a sign of genius; in a woman, it’s a profound failing. Masters never has to take his hair down or flirt with a provost. There’ll always be someone to clean up his mess and make him sandwiches. He and his work won’t disappear because no one would ever allow it. He can’t slip through the cracks, because he’s continually carried right over them.

That Masters of Sex never shies away from this rough truth is to its great credit. What Virginia pulls off at the country club is absolutely a victory but, due to gender and circumstance, she and Lillian aren’t even playing on the same field as Masters and the other men. They’re not even playing the same game. Pluck is great. Competence is even better. (That said, how fascinating was the minor scene with the doctors’ wives? It was a glimpse of a shadow Mad Men, one fully invested in the hopes and dreams of the Jane Sterlings and Megan Drapers of the world, not just what they might mean for their hard-charging spouses.) There was such sadness in Nicholson’s eyes when Lillian revealed her condition to Virginia on the bus ride home. Not so much because she would die before her work was finished, but because she was born too soon to have a chance at the modern life Virginia is determined to forge. The show is too complex to suggest that a brighter future depends on all women becoming as chameleonic as Gini. The real victory is when not all women are required to be that way in order to thrive.

Which isn’t to suggest that the men of Masters of Sex have it easy. They just have it infinitely easier. The collision of Ethan and George was about individuals cursed with too many choices, not too few. Ethan is secure enough in his prospects to be unemployed for a spell, to give up a promising engagement, to treat the unknown as an opportunity, not a trap. (He’s also able, in the course of a season, to transition from an unctuous creep who punches women into a domestic boy scout. I think the show has done the best it possibly can with this metamorphosis, but I don’t forgive the character nearly as easily as Gini appears to have done. Redemption, I guess, is just another unexamined male privilege.) Mather Zickel is a wonderfully louche presence as George, Virginia’s boomerang of an ex; his heartache over the kids he loves but never really wanted is real and deeply felt. But, again, his is a suffering of choice. If he wants to keep living life on the margins, it’s his prerogative to do so. No one is taking his children away from him. He’s taking himself wherever he wants to go.

It’s grace notes like these that, in a relatively short amount of time, have elevated Masters of Sex into one of the best shows on television. The performances are uniformly excellent: Lizzy Caplan is doing the best work of her career by forgoing her trademark dash of bitters; her Virginia, like the show itself, is a model of patience and precision. And Michael Sheen’s work is no less remarkable; I see now that his choices in the early episodes were about constructing a suitably imposing façade for this great man, just to occasionally let it crumble, thus providing a glimpse of the scared boy underneath. But, as with the real Masters and Johnson, the work here goes beyond that of the two leads. The traditional medical show tends to contrast the stuffiness of medicine with the hot unpredictability of people and the real world. What Masters does so brilliantly is invert our expectations. Its vision of the 1950s is as rigorous and prescribed as any laboratory. Roles are accepted, convention is obeyed. The anarchy of experimentation only truly exists within the ivy-covered walls of academia. It’s there and only there where the strict imprimatur of science allows for all the messiness of life. As we head toward the season finale — and the promise of many more seasons to come — Masters of Sex has proven itself to be so much more than another drab period piece. It’s not about a dutiful depiction of a faraway world. It’s about the prosaic, often uncomfortable invention of our own.