Matthew Rhys. Photo-Illustration: Vulture and Photos by Eric Liebowitz/FX

“I guess you never really know a person, do you?”

An FBI field-office secretary named Martha poses that question in season four of The Americans. The delivery, by actress Alison Wright, is muted, devoid of self-consciousness, like nearly every line on this modestly excellent series, and that’s why it lands with such force. Every major character harbors multiple secrets and sustains multiple lies. They’re interwoven so deftly by series creator Joe Weisberg, his co-executive producer Joel Fields, and their cast and crew, that whenever fate tugs at a frayed strand and somebody’s life starts to unravel, you’re invariably surprised and appalled, even though The Americans has made an art of exploring the peril and necessity of deception, never shying away from the collateral damage it inflicts. Melding the prosaic and the metaphorical, the mundane and the absurd, always with a poker face, the series has gotten sharper and more confident by the week. It now carries itself with such relaxed confidence, it can build to a tragic twist so subtly that you simultaneously wipe away a tear and laugh at yourself for not seeing it coming from a continent away.

There are so many secrets and lies on display that the show is always also about the performance of life even when it’s telling tales of mayhem and intrigue. The main couple, Philip and Elizabeth Jennings (Matthew Rhys and Keri Russell), pretend they’re suburban D.C. travel agents, but really they’re Soviet spies, trained to impersonate Yankees and sow disorder for Mother Russia. They’re masters of assassination, theft, seduction, and disguise (their awesome array of wigs has become a running joke among fans), but because they have to integrate their missions into a façade of normalcy, you rarely think about how super-competent they are. Their more security-sensitive discussions happen in the kitchen of their nondescript split-level suburban home (when the kids are at school) or in an adjacent laundry room (when the kids are at home or asleep). A typical scene in season four finds Philip and Elizabeth in disguise, sitting in an outdoor café waiting for a contact to walk by, killing time by discussing the suffocating cologne their son, Henry (Keidrich Sellati), has started wearing. Despite all the killing and screwing and sneaking around they do on the motherland’s behalf, Ian Fleming might find them sad, but John le Carré would feel for them.

From The Twilight Zone to The Sopranos and beyond, some of the greatest television shows have found ways to lift basic human predicaments out of their familiar contexts and deposit them in alien scenarios, so that we see their essence etched in sharp relief against a background of contrivance. The Americans does this as well as any show in TV history, and with more modesty than many of its predecessors. It has a knack for creating metaphorically or symbolically rich situations that never strut about announcing themselves as such. It’s all there if you care to delve into it, but it’s never in the foreground and affixed with a tag; often you catch it hiding behind, or within, the characterizations and plot twists, as spies hide in plain sight.

Fields and Weisberg often seem surprised when viewers find more than one or two levels in any scene or subplot, which suggests that everyone involved with the series is committed to being, or seeming, like a meat-and-potatoes TV show, the kind of thing that might air on CBS. The ebb and flow of Philip and Elizabeth’s marriage and their children’s relationship to them and to the truth; Stan’s fluctuating feelings of dedication and ennui, patriotism, and cynical disgust; Nina’s alternations of hope and despair, romanticism, and regret; the sense of the former Soviet Union and the United States as parent-states using and abusing their “children” in the name of global dominance: These touches and others come through in crisply written and directed scenes of people going about their (often ridiculous) business as if they aren’t characters on a TV show; as if they’re just like anybody else.

The exceptional cast benefits from the writers’ no-fuss attitude toward metaphor, simile, and all that other fiction-workshop stuff. They can just be the characters, and let the additional layers accrue organically, often imperceptibly, over time. If you could watch Rhys’s extraordinarily detailed performance in time-lapse over four seasons, you would see a character’s soul wilting like a flower deprived of water and sunlight. Russell, whose character was at first stereotyped as “the cold one” of the duo, complements Rhys’s raised-antennae empathy. Her performance suggests that she keeps Elizabeth’s own tragic history, which includes a traumatic separation from her parents and a rape at the hands of a KGB handler, close to her consciousness. The ebb and flow of their marriage has been portrayed with intelligence and subtlety, despite all the scenes of Philip and/or Elizabeth having sex with a potential source or murdering somebody in the dead of night. When the show began, the Jenningses’ union appeared to be at a crisis point, with Elizabeth fiercely committed to the motherland and Philip falling for the allure of American comfort, excess, and showmanship (all three came together in the pilot, when Philip did a boot-scooting dance in a department store to Juice Newton’s “Queen of Hearts”). Now they seem to be closer than ever, which makes sense when you think about how the walls have started closing in around their potential for transformation or escape. All they have is each other, and their kids.

Stan Beeman (Noah Emmerich), an FBI agent who used to live down the block from the Jenningses, is another mundane-fantastic creation. He’s still suffering post-traumatic stress disorder from his undercover days. He once murdered a Soviet bureaucrat to avenge a colleague’s murder (by Philip, though Stan doesn’t know that). And he’s spent the last season pining over his deported Soviet lover, Nina (Annet Mahendru), whom he turned into a double agent, and who later became a triple agent before getting convicted of treason and shipped to a Soviet gulag. Like Russell, Rhys, Taylor, and Sellati, Emmerich invests Stan with such beaten-down gravitas that you think of the character not as a brooding super-cop, but a grumpy working stiff: a divorced, depressed, gifted-but-mercurial problem employee; a man who starts his own unauthorized investigations partly out of frustration with FBI inertia, but mostly because he’s bored and depressed and needs to fill his lonely hours with something besides booze and self-loathing.

The not-funny funniness of The Americans, a show stocked with refreshingly un-self-aware characters, comes through most clearly in Stan’s scenes. Even more so than Philip and Elizabeth and their kids, he has no sense of humor about himself, indeed no apparent notion of how he appears to other people. Whenever Stan and Nina’s other lover, Oleg (Costa Ronin), a high-ranking employee of the Soviet Rezidentura, meet to discuss Nina’s fate, their conversations are hushed and awkward but charged with yearning. Equally fine and funny are the scenes between the towering Stan, who has the classic middle-American swagger of a gym teacher who calls every student by their last name, and the much shorter Philip, who can slip into a convincing impersonation of a milquetoast American white guy but is a trained killer who could crush Stan’s windpipe with a single well-timed punch. Stan has no idea that Philip and Elizabeth are Soviet spies, or that they’re responsible for his partner’s death, or that Philip is secretly married to his colleague Martha (under the assumed name of Clark, as in Kent), and persuaded her to steal information from the FBI office by convincing her that he’s a U.S. government agent investigating corruption.

Season four’s main story builds on season three’s most momentous development: Elizabeth and Philip’s decision to tell the increasingly suspicious Paige (Holly Taylor) the truth about why they’re always sneaking around at night and coming back with torn clothes and bruises. Paige had previously rebelled against her openly atheist parents by joining a left-leaning Christian youth organization and protesting nuclear proliferation; in the season-three finale, she tells her most trusted adult confidante, her youth pastor Father Tim (Kelly AuCoin), the truth about her family, because it’s eating her up inside. Now, Paige’s parents and their handler, Gabriel (Frank Langella), have to decide how to handle this security breach. The obvious solution is to kill the pastor and make it look like an accident, but if they do that Paige will realize what happened and maybe melt down and complicate things further, and then what can they do, really? Kill Paige? Relocate to the U.S.S.R.? This plot is yet another example of The Americans’ complicated attitude toward deception: It is often justified and subjectively necessary, but at the same time it poisons every life it touches — even the lives of people who have no idea a deception is being perpetrated, much less the extent of it.

Much of Philip and Elizabeth’s season-four spycraft is in the service of obtaining purloined samples of biological agents. A “biological agent” is, of course, what Paige will one day become, if Gabriel and his bosses back in Moscow have their way. The looming threat of a pathogen contaminating an unsuspecting civilian population also becomes an unfussy metaphor for how the Jenningses’ sustained, multivalent acts of deception leach into every relationship in their lives, including their marriage. In an unbearably sad moment this season, Martha goes out to dinner with a co-worker and confesses that she’s in a relationship with a married man. The lie bears no relation to anything that’s actually happening in Martha’s life, yet it describes her situation perfectly. Like The Americans itself, this lie is a fiction that’s so true it hurts.

*This article appears in the March 21, 2016 issue of New York Magazine.