David Bloomer/Showtime

It's possible Carrie Mathison is a good person. Perhaps she's actually smart, intuitive, a creative thinker, and an asset to U.S. intelligence. It's even conceivable that, when effectively medicated for longer than a month at a time, she's reasonable, curious, and not so sociopathically detached from the world outside her own brain. But if she actually is any of these things, rather than just callous, impulsive, rude, and frequently hysterical, we wouldn't know. What last night's episode of Homeland, "Redux," proved is that the show has nothing for Carrie to do as a functioning human being, which is why her mental illness is exploited with such tiresome regularity once a season.

It's easy to see why a drama that's made its mission to get people to sit bolt upright in their armchairs every Sunday night might find its main character's bipolar disorder irresistible: off the leash/Klonopin, manic Carrie gets into all kinds of high-octane scrapes, from screaming at her ex-lover's daughter in a driveway in suburban Virginia to storming into a newsroom and telling a befuddled reporter that Brody's actually innocent. But from the viewer's perspective, it's exhausting. Not to mention that the events of "Redux"—wherein Pakistani intelligence agents were able to replace Carrie's real meds with trippy psychedelic ones, prompting a spectacular breakdown—are exactly why someone so vulnerable shouldn't be in the CIA (let alone station chief of Islamabad) in the first place.

Last night's preposterous climax, in which (spoilers obviously ahead) a delusional Carrie was kidnapped by goons, forced into a straightjacket, and left alone in a room to wait for a man who appeared to be Nicholas Brody, was obviously intended to poke fun at all the speculation at the end of last season about whether Brody was actually dead. But the fact that it wasn't impossible to imagine for a second that the show would bring him back only points out how ridiculous Homeland has become. Yes, Brody was a hallucination, just like Carrie headbutting Quinn and breaking his nose before rushing into the street and shooting two men who appeared to be following her was (hopefully) all imaginary, too. That the show once billed as "the thinking man's 24" is now reduced to bringing back departed stars, Bobby Ewing-style, in a fever dream encapsulates just how far from seriousness it's deviated.

It isn't just Carrie: Homeland seems to have given up on trying to make any of its characters good at their jobs. There's Saul, who fell for the oldest spy trick in the book when he followed Farhad Ghazi into the men's room at Benazir Bhutto International Airport and got himself kidnapped in the process. (Efficiency aside, would an Islamic fundamentalist really have sex with his wife and force the former director of the CIA to watch? Why? That scene felt like a sop to the glory days of Showtime, when every episode of every drama had to have at least once instance of full-frontal nudity.) There's Peter, who doesn't do anything anymore apart from roll his eyes and judge Carrie. There's Lockhart, who sparked a major diplomatic incident when he threatened to take away Pakistan's $2 billion a year in aid before returning to his game of Words With Friends. And there's the shifty, wormlike Dennis Boyd, who peers through keyholes and creeps through other people's bedrooms with all the subtlety of a plain-clothes Hamburglar.

Part of the problem of this season, something that isn't really the show's fault, is that America's attention has drifted from Pakistan and Afghanistan and headed to the Levant. Had Homeland set season four in Washington, or Yemen, or Beirut, or even London, it wouldn't feel so removed from actual events. Instead it seems like next week's episode is going to feature an ISIS-style kidnapping video of Saul in front of a black-and-white flag in an attempt to remain relevant. But no locale or storyline could make up for the fact that Homeland doesn't know what to do with its characters when they're not losing their minds. And that's a problem.

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