Last night's episode of The Americans, "The Midges," was packed with corrosive action: Elizabeth and Philip danced to country music in Oklahoma and grilled and killed a lab administrator. Paige, looped into a mission her parents thought was relatively innocuous, implemented "the technique" and lied successfully to Matthew. Like Russia's wheat crop, Oleg Burov is being targeted by lethal American pests — and targeting purveyors of food that's too good in turn. But the most thrilling revelation might have been that glimpse of Martha Hanson (Alison Wright) in Moscow, shopping at a grocery store whose supply line Oleg is investigating. The camera has been especially playful this season — sneaking up on Tuan and Pasha from behind the cafeteria food, tricking us into discovering Elizabeth and Philip are playing his parents — and the way it lingered on Martha's back instead of trotting after Oleg, whom it followed into the store, is a lovely instance of the way various plotlines are getting dropped and picked up in this, the show's penultimate season.

The joke of that shot is that the camera picked up on something we didn't; a clever agent in its own right, it recognized Martha and waited for us to catch up. Thank goodness it did: Martha in the USSR is a spinoff I'd watch, and her reappearance doubles as a crucial reminder of the many loose ends with which this series is packed. I've been missing those this season. The energy that's gone into establishing the Morozov mission, coupled with the show's new thematic interest in hunger, temporarily sidelined the longer, more psychologically driven plots that make The Americans great. I'm talking about things like the peculiar strains on the Jennings' marriage, the ongoing threat of Pastor Tim and Paige's struggles to perform normalcy with him, the yearnings that drove Philip to EST, and the uncharacteristically raw fragility Elizabeth displayed last season when she and Paige visited her mother. All that gets sidelined by a call to action — the Jennings are pros, after all — but I'm hoping we get back to those quieter, more complicated tensions.

The revelation that Martha is alive and struggling to read Russian packaging in a grocery store comes at exactly the right time: It confirms, for one thing, that the Centre meant it when they said they'd take care of her. (This has long been a big question: Is Gabriel on the level? How much weight do his promises carry?) The Centre kept its word, even if the FBI and CIA won't. Stan's insistence that they need to "play by the rules" and leave Burov alone underlines the deterioration of any code of conduct that might once have guided the CIA and the FBI — a point reinforced by Philip's consternation at the news of the wheat-killing pest: "Going after people's food? I thought there were things they wouldn't do," he said. It's a perfect complicating note, then, that the KGB is a) "going after" people's food back in the USSR, albeit in a slightly different way, and b) treating the American who helped them well at the very moment the CIA is going after the Russian agent who helped them. (Interesting, too, that neither the FBI nor the CIA have realized that the Russians got what they wanted anyway — from William's corpse.)

Martha's reappearance reminds us, too, of how far apart Elizabeth and Philip drifted when he was married to her. Where are they now with respect to their marriage? There are hints that they're closer than ever, at least professionally: I rewatched the scenes in which they tacitly agree to kill Hans and the lab tech for tells that would let me see the moment they agreed to pull the trigger — the code they're using to privately confer. I couldn't spot it. They're so attuned to each other that their exchange is basically invisible to the viewer. But that still leaves open the question of their private allegiances and the state of their bond: Of whom do they think when they rub their thumb and forefinger together in moments of confusion. Do they think of their families? Of each other?

Last season ended with the possibility of the Jennings clan returning home; it began anticlimactically, with them still here, repurposed into a parallel version of themselves. But there hasn't been much time for them to reconnect. It's beautifully weird, then, to watch them rekindle over an Oklahoma that reminds them of home — while role-playing to a country-western song.

The true test of a series is how it handles its loose ends. It's encouraging to watch The Americans start threading its longest and oldest storylines into the present. Even the episode titles this season seem to hint at the way old ideas keep getting whittled down to painful particularity in the present: "Amber Waves" was about food and nationhood in the abstract, but "Pests" was about the horror of a swarm when it's disturbed, and "Midges" digs into the particulars of a pest tailor-made to cause maximal destruction to be delivered via undetectable eggs. The reproductive capacity is destructive here, and while Philip and Elizabeth have been able to remain American abstractions ("The Americans," even) for a long time, they've been eroding into particularity for awhile — into Nadezhda of Smolensk and Mischa, who once dated Irina.

And as Philip's son makes his way slowly and with difficulty to America, the show seems to be preparing for them to deal with the loosest end of all.