Homeland's season three endgame is finally coming into view. And as was the case in the first two seasons, the focus is on Nicholas Brody.

This is one messy character to have at the center of your plot. He whines, he vomits, he breaks furniture and stabs his arm, he craps all over himself and cries, he hallucinates, he jogs, and ultimately, he flies to Iran to kill a man.

Sunday's "One Last Time" is the second episode this season that substantially features the ex-Marine/ex-congressman/ex-terrorist — and the first to include his interactions with the rest of the cast. He is a complete train wreck of a human now that Saul has dragged him back to the mid-Atlantic from Venezuela. Heroin kept him going as a prisoner there, and now he's going through sickening, disturbing levels of withdrawal. The first half of the episode is genuinely troubling to watch. Did anyone know Damien Lewis's voice could grow quite so childlike and pitiful as he gyrates in his Virginia cell with Saul's men?

This is all part of Saul's Grand Plan — which seems ever more more addled, and without any real insight in its calculations. This whole season has been, to a greater or lesser extent, about trusting in Saul's goals. Everything, from Carrie's faux-instability to the Majid Javadi ploy to Brody's training, have served his plan, which inexplicably appears to be working despite a general lack of coherence.

The biggest blip of cognitive dissonance is exactly what caused Sen. Andrew Lockhart to ask if Saul was high a couple episodes back. Saul's real endgame seems to involve putting Javadi in power in Iran — a maneuver he believes will change the calculus in U.S.-Iran relations for the better. Of course Javadi has the potential to be a valuable asset. But the way Saul talks about it seems clueless. He lights up when explaining his dream to Carrie. Put Javadi in charge, and sure enough, "the logjam" ends, Saul says. The constant war of back-and-forth terrorism ends. The countries can sit and talk.

Really? You're staking this on Javadi? Saul may have befriended the Iranian intelligence chief decades ago, but this is the man who killed his own wife and daughter-in-law this season just to stick it to Saul. Yes, Javadi may be useful if he'll work with U.S. officials — but to assume he'll be a peaceful cooperative is beyond baffling.

To put Javadi in power, Saul wants to send Nick Brody to Iran to seek asylum as the Langley bomber (which, by all accounts, he is not) and proceed to assassinate Javadi's boss. But of course, there are obstacles. Heroin addiction, for one, and Saul's expiration date as acting CIA director for another (six days left at the episode's outset until Senator Lockhart's confirmation hearing!). "He's not what we expected," Saul murmurs when watching the withdrawn wreck that used to be Brody quivering in a cell.

Luckily, Homeland always magically rescues key characters when they're most in need, and Brody doesn't just collapse and die. Saul decides to give him a withdrawal-reducing substance that, alas, comes with "violent, mind-bending hallucinations." That decision allows viewers to see a shaky Brody imagining himself face to face with former Marine turned terrorist Tom Walker, as well as other flashbacks to his life imprisoned in the Middle East. It works out great for Saul, who speeds Brody's recovery while coming off as the hard boss who will do what he has to achieve the grander goals.

And fortuitously for everyone, Saul is able to buy weeks of time to get Brody ready. He discovers (surprise!) that Lockhart has used Saul's wife's lover to bug Saul's home. Postpone the confirmation hearing until the middle of next month, Saul tells the senator as he unveils incriminating photos — leading to a montage of Brody running and training and turning into a skilled Marine again over the course of two weeks.

From a sheer popcorn drama level, "One Last Time" delivers. It's riveting to see Brody back in the mix, and his psychological state is truly singular. This is a onetime terrorist who the world hates for a bombing he never actually committed. To say he lacks prospects is the understatement of the century. Brody absolutely has no choice other than to cooperate with the CIA's harebrained assassin plot — despite his very logical fears about how he'll escape Iran after killing a top Iranian official. And as a side note, let's not forget that Saul's big scheme to end terrorism between the U.S. and Iran is starting with an assassination.

Nick Brody stays the king of hubris. Reckless pride has always propelled his character; a belief that he is strong enough and wise enough to do what's right, even if it means strapping a bomb to himself surrounded by leaders of his home country. Carrie first gives him a glimpse of his daughter Dana, who now works as a motel maid and has changed her last name to Lazaro. Thanks to Carrie's benevolence, he finally gets his chance hours before he leaves for Iran. Though he knows that Dana tried to kill herself after his alleged bombing at Langley, Brody goes right up to her motel room and knocks.

But Dana — in a turn that comes close to justifying all the long Brody family sequences earlier in the season — spurns Brody completely. "Did you ever for one second think about whether I wanted to see you?" she asks in tears. She scoffs at his presence and wonders if he wants her to say what a good dad he was. The moment somehow leaves Brody all the more steeled in the car. He assures Carrie that, yes, he'll be coming back from Tehran.

Yet despite these Carrie and Brody encounters, "One Last Time" is no lovers' reunion. Carrie sent Brody off last season with a sense of crushed romance. But now — months later and pregnant with Brody's child — Carrie doesn't so much as move to kiss him, and she doesn't tell him about her pregnancy. Brody is ready to rebel against any captor at this juncture, and those captors include Carrie, who is dispatched as another of Saul's tools to control Brody. Now let's hold our breath for the meeting of Brody and Javadi in Iran. Will that actual mastermind behind the Langley bombing treat the ex-Marine so gently? Don't bet on it.

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