THE AMERICANS Photo: Craig Blankenhorn

Midway through what was already one of the best weeks for scripted TV since I became a TV critic, The Americans wrapped up one of the best second seasons of a drama I can recall. Written by creator Joe Weisberg and co-executive producer Joel Fields and directed by Daniel Sackheim, it was called “The Echo,” and like so many titles of Americans episodes, this one subtly teased out more than one definition. The most resonant is the idea that children are echoes of their parents, and that (incidentally or by design) the next generation in a country’s ideology is an echo of the one that came before.

That’s what makes the episode’s climactic revelation so powerful: The same people who employ Philip and Elizabeth Jennings as spies are looking to claim their genetic echoes, their kids, beginning with their eldest, Paige. The first apparent test case in this new program was Jared, the sole survivor of the theme park massacre that killed his spy parents and his sister and that we never imagined could be his own handiwork. It was, apparently, the work of a full indoctrinated zealot, a next-generation, kill-for-Mother-Russia true believer. This is what the program wants to turn Paige into: a sleeper agent who can dig deeper into U.S. institutions and do more damage because she’s a bona fide citizen with a domestic paper trail and thus a better bet to pass high-level security checks. Get ‘em while they’re young.

This is the frighteningly logical extension of the drumbeat that Elizabeth has been sending out since the pilot, and that she’s hit harder during season two, in the face of her husband’s qualms about the civilians he’s snuffed out: When you believe in a cause (in this case the advancement of communism and Soviet state power) you advance it by any means necessary. You chalk up any momentary guilt or regret you feel over violent, sexual, financial, or other transgressions as byproducts of the larger mission — eggs broken for the omelet’s sake. One person’s fanaticism is another’s commitment. But what will this cost the Jenningses? Their marriage? Their children? Their lives?

You get the sense that this series could go anywhere, but that wherever it goes, the plot twists will be motivated not by expediency but by a fully worked-out vision that welds politics and history to morality and philosophy. The Americans is unabashedly a popular entertainment, moving from plot twist to plot twist and making sure to build a certain number of killings, sex scenes and double-crosses into each episode. But none of them feel like arbitrary time-wasters.

The sex scenes have real heat but also real implications for the marriage. This season, Philip has grown increasingly uncomfortable with Elizabeth’s skill at what intelligence agents call “honey trap” operations. This is the logical outgrowth of their fake marriage turning into a real one this season; the new era began during that sex scene in the pilot after they disposed of her rapist’s body, and took a quantum leap forward this year as they both became increasingly worried about the behavior of their kids, Paige (who ran off without permission and got involved in a politically active church group) and Henry (who busted into a neighbor’s house to play the video games that his parents wouldn’t buy him). It might have started out as a cover story, but the Jennings family is a real family now. In terms of parent-child relations, it always was. That part’s never been fake. Now the marriage feels more real. Some of the best moments this season found Philip and Elizabeth just talking to each other, after sex or while killing time during a stakeout. (The season finale had one of my favorites: He talked about being harassed by gangs in Tobolsk, and she talked about nursing her mother through diphtheria, and you might’ve have thought it strange that neither had told the other these stories if you didn’t already know their strange history.)

The increased realness (or “realness”) of the marriage seems to have heightened certain anxieties in Philip. His behavior around his “wife” Martha (for whom he impersonates the bespectacled, slightly nebbishy Clark) seems to unbalance him even when he’s trying to be as cold and detached as possible. It’s as if, in pretending to be a good husband in order to use her as an asset, he can’t help feeling as though he really is married to her. He’s a Russian pretending to be a married American and is growing to feel as if he really is a married American, even as he impersonates an American spy in a legally “real” marriage. That’s an acting challenge I doubt anyone could keep straight. At one point Martha tells Clark she knows he wears a toupee — a nifty acknowledgment of the show’s sometimes ludicrous disguises that doubles as a tender moment between two married people. (I nearly put the word married in quotes, then remembered that in legal terms they actually are married; this show sure plays games with your head.) “Clark” admits to Martha that he doesn’t want children — a possible deal-breaker for her. The mix of emotions in his eyes is wondrous to behold: relief at not having to have kids with her, sadness at letting her down, and something else. Maybe fear that he’ll have to get her pregnant anyway, to keep her on the intelligence hook?

Performance is everything on The Americans. The performances have layers upon layers upon layers. Sometimes — as in Philip/Clark’s marriage to Martha — you’re watching a performance within a performance within a performance. And it’s not just the according-to-Hoyle spies who are acting their asses off. Nina is doing it with Stan, as part of the triangle with Oleg. She was pretending to be in love with him, but she really was in love with him — or at least she loved him. How much real affection was there between her and Oleg? A fair amount, or so it seemed to me, though I was disappointed in him personally that he didn’t seem more broken up as she left the Rezidentura. The final exchange of glances between Nina, being driven to the airport to return to Russia, and Stan, watching from a parked car, was devastating: a French Lieutenant’s Woman moment. Even Larrick, the murderous SEAL who nearly kills the main couple, and Jared, the massacre survivor, are giving performances, hiding their true selves from their bosses, and their true motives from nearly everyone.

The secret star of The Americans is its filmmaking. This season’s list of directors included some of series television’s heavy-hitters: Sackheim, Thomas Schlamme, Lodge Kerrigan, John Dahl, former Sopranos director and cinematographer Alik Sakharov, Gregory Hoblit. They’re all working within a template that apes an extremely specific period in American dramatic features, roughly the late ‘70s through the mid-’80s, but within that template you see all sorts of grace notes and dramatically motivated flourishes, including wide master shots that emphasize the oppressive layout of institutions and their adjunct spaces (notably the brass-and-oak Rezidentura, the fluorescent-lit FBI agency, the blandly functional suburban homes of the Beemans and Jenningses, and Stan and Nina’s poignantly minimalist love nest). Some shots highlight the converging perspective lines of walls, ceilings, roads, and bridges. Others seem to flatten beleaguered characters between foreground and background elements. All recall the work of the late, great Gordon Willis, who shot some of the best paranoid thrillers of the ‘70s, including The Parallax View, which I sometimes think might be a primary influence on this show’s visuals. (Just look at this and this. And this.) The show’s not big on ostentatiously spectacular camera moves, but there are so many that impress. One of my favorite ones appeared in last night’s finale: a pan that followed Philip as he walked to his car, then stopped on his reflection in a car window, revealing Larrick standing behind him.

I can’t imagine where The Americans will go from here, but I have a feeling it has nowhere to go but up. It’s exciting to realize that the show is capable of anything but won’t do just anything. Everything is motivated. Nothing is purely for effect. It’s as efficient as a series can be and still have the pulse of life.