Despite her limited screen time, the fabulous Mrs. Gaines is actually one of the more significant characters on Homeland. Not so much for what she does — getting driven around by a chauffeur, calling the room with the television in it “the library” — but for what she represents. With her casual omniscience (she’s somehow aware that Saul’s wife is leaving him in the morning, despite Saul possessing the social life of an ornery hermit crab) and her entitled, behind-the-scenes gamesmanship (“Brody for Congress” posters are practically being printed before she even informs the Sergeant of her plans), she’s a silvery glimpse of the real power that lurks just beyond the reach of our intelligence-starved intelligence gatherers. Mrs. Gaines, like the feared Abu Nazir, operates on a higher level than Carrie, Estes, and even poor, desperate Brody. What may seem like gobsmacking surprises to those of us at home — Dick Johnson’s (!) sexting scandal or the fact that Tom Walker, Brody’s former POW punching bag, is alive and not exactly well — are, in actuality, all part of the larger chess game, one being played at a level that far exceeds our security clearance. This makes life hard for our heroes, but it’s a rare gift for television fans. Contemporary dramas are more dependent on twists than Chubby Checker’s estate planner — recent misfires like The Killing preferred gotcha games to coherent storytelling. What separates Homeland as it hurtles breathlessly toward its first-season finale is that there really seems to be a plan in place, a strong, character-based foundation able to support the head-spinning developments. Showrunners Howard Gordon and Alex Gansa might not be as evil as their fellow string-puller Abu Nazir, but they’re proving themselves to be equally thorough.

After last episode’s paranoid weekend in the country, “Achilles Heel” snaps us back to the big city. Despite Brody’s knuckle-busting memory, it seems Tom Walker truly is still breathing and, in a nefarious turn of events, has been placed on the streets of D.C. under deep cover as Tyrone Biggums. Walker’s one weakness isn’t personal hygiene, though. It’s love for his family. We learn that, between hustling commuters for loose change and plotting the assassination of the president, he’s been stalking his son at school (leave it to Estes to get the truly tough interrogating jobs) and crank-calling his own answering machine just to hear familiar voices. After some standard-issue CIA/FBI catfighting (girls, girls, you’re both extrajudicial!), a plan is agreed upon: Carrie, using Saul’s best ideas, will head up a mission to entrap Walker via cell phone. Everything works perfectly, of course, until it doesn’t: Walker hangs up the first time (leaving the Feds the way Saul likes them, “standing around with their dicks in their hands”), but, later that night, he stays on the line while his would-be widow, Helen, pours her heart out and the Langley geeks triangulate. So effective is she in dredging up old emotions that she loses herself, warning Walker at the very last minute what she’s done. After a chaotic chase, Walker leads his FBI pursuers to the best possible hiding place for him and the very worst for them: a local mosque. A few unfortunate bullets later and two dead Muslims are being retrofitted as press-friendly terrorists while the real baddie remains on the lam.

Walker’s soft spot isn’t his alone, of course; poor Saul is equally devoted to a wife he hasn’t got any time for. While Walker heads to a storage facility to pick up his sniper rifle in lieu of redialing, Saul chooses to spend his last night as a married man squiring Mira to Mrs. Gaines’ sceney soiree. There, while his wife mingles, he sadly downs a glass of bubbly and makes himself “useful” to his hostess by playing valet. Work is everything to the characters on Homeland on both sides of the ball. It’s been a well-woven theme of the show thus far, that the very things that make these characters human — honest relationships, diets free of expired spaghetti sauce — are directly at odds with the requirements of global terrorism and/or counterterrorism. It was Brody’s alienation from his family these past seven weeks that allowed us to assume his guilt; his changed demeanor post-Carrie (and post-Carrie confession) — spending last night playing dress-up with his wife and munching popcorn with his kids — lulled us into a false sense of (national) security. It wasn’t the emergence of Walker that made us buy Brody’s innocence; it was his casual joking about a cartoon. As Carrie, who began the episode coming clean but ended it with everything much, much messier, admits to a silent Saul, “I’m gonna be alone my whole life, aren’t I?” Real players in this game don’t have time for meaningful connections. A working knowledge of the difference between animated elephants and mastodons? Forget it.

Of course, there was one last turn to be played: With the Walker story public, we’re expecting to find him huddled on the couch in the evil diplomat’s TV room (it’s what Mrs. Gaines would call a classic library). But no: It’s Brody. He half-strangles the devious beardo, announcing, “I’m through talking with Abu Nazir. It’s over.” As he stalks off, Brody’s motives are muddier than ever. Was he a beaten-down and beaten-up patsy? A fail-safe for Walker’s flashier mission? Or something else entirely? At work, alone at last with each other, Carrie and Saul are inundated with false leads and dead ends. Time is running out for them to uncover the master plan. As fans of quality TV, we should take pleasure in the fact that there is one in the first place.