On Oct. 22, Showtime renewed Homeland a few episodes into its third season.

At the time, the deal seemed like a mistake—or at least a decision that had more to do with commercial considerations than creative vitality. The terrorism drama was mired in a slow-motion subplot about Dana Brody’s (Morgan Saylor) loose-cannon boyfriend, Leo; meanwhile, Carrie Mathison (Claire Danes) was still stuck in a mental institution, trembling chin and all. A once-gripping show had become kind of monotonous, and I for one wasn’t particularly excited by the prospect of a Season 4.

But after watching Sunday night’s installment, I’ve finally changed my mind. “Big Man in Tehran” was easily the best episode of Homeland since the first half of Season 2, and it proved once and for all that the series hasn’t jumped the shark. Quite the opposite, in fact: Homeland is now back on track, with a clear path forward. I can’t wait for Season 4.

Assuming, that is, that creator Alex Gansa & Co. don’t screw up next week’s finale.

Sunday’s episode illustrated both the peril and the promise of Homeland’s make-or-break moment.

(Warning: spoilers ahead.)

As I recently wrote, the show is at its best when it’s all about “Carrie and Saul Berenson (Mandy Patinkin) and the spy games they play.”

And that’s what “Big Man in Tehran” was all about. In the preceding episodes, Saul and Carrie had turned the high-level Iranian intelligence officer Majid Javadi. They had transported their asset to Iran undetected. They had launched a plan to get Brody (Damian Lewis), now a CIA plant, into Tehran to assassinate Javadi’s boss, General Danesh Akbari (a.k.a. the head of the Iranian Revolutionary Guard)—all so that Javadi could take his place and reset Iranian-American relations. Now they just had to execute.

This scheme, of course, is fanciful. But Homeland isn’t literature, and it never has been. It’s pulp fiction—smart pulp fiction, but pulp fiction all the same. And here’s the thing about pulp fiction: it doesn’t really work unless it’s page-turning stuff. Which is why I never really cared whether Saul’s plot to end the global War on Terrorism was realistic. After half a season of molasses-y, misdirected character development, the Javadi play got Homeland’s pages turning again. That was good enough for me.

I loved “Big Man in Tehran” for the same reason. It was this season’s most page-turning installment—the episode in which all the storylines that Gansa and his team began to weave into the series earlier this season finally tied themselves in the kind of narrative knot that you can’t wait to see untangled. Javadi had to convince Akbari to meet Brody in person. Carrie had to pass a lethal Mossad device to Brody so he could off Akbari once the two of them rendezvoused. Brody had to recalibrate when Akbari head faked in a public square and enlisted Abu Nazir’s widow to vet him instead. And finally Brody had to choose sides after spending months as a propaganda mouthpiece in Tehran, denouncing the U.S. on television. When Brody entered Akbari’s office at the end of the episode, I honestly didn’t know whether he was going to rat out Javadi or assassinate the general. That’s a testament to the renewed skill of Homeland’s storytelling.

And yet, “Big Man in Tehran” also illustrated how Homeland could go wrong in next week’s finale. As my friend Phil Maciak has written, “letting Brody live past the first season” was Homeland’s “original sin.” Lewis knows it. Even Gansa kind of knows it. By keeping Brody alive, Gansa and his team have forced themselves to elongate his romantic relationship with Carrie as well. First they’re enemies. Then they’re lovers. Then they’re enemies again. Then they’re really in love. And now Carrie is pregnant. Every time that baby kicks—as it did Sunday night when Carrie was on the phone with Saul from Tehran—it serves as a reminder of how ordinary Homeland can be: a show that’s behaved more like a second-rate sitcom than a premium cable drama by opportunistically extending a romance well past its expiration date.

o next week’s finale can go one of two ways: it can follow the silly logic of a television love story and reunite Carrie and Brody yet again—two new parents on the run—or it can adhere to the less forgiving logic of international espionage—Saul’s extraction plan was always implausible, wasn’t it?—and kill Brody in Tehran.

I predict that Homeland will pick Door No. 2. Carrie will lose her baby daddy, triggering the kind of emotional anguish on which her character thrives—plus another lifestyle conundrum for the writers to mine in future episodes (Carrie isn’t just a bipolar CIA agent; she’s also a single mother in the workplace!). Maybe she’ll rage against the CIA for failing Brody as well. Saul, meanwhile, will notch a huge PR victory—the scalp of the Langley bomber—so perhaps he’ll leapfrog Sen. Lockhart to become CIA chief, reorienting the show around Javadi and Iran—a much more interesting subject than Al Qaeda. Finally, and most importantly, F. Murray Abraham will continue to lurk in the shadows, looking mysterious and bald.

Which is why I’m looking forward to Season 4 all of a sudden. One more week to see if Homeland can stick the landing.