On this week's episode of Homeland, we learned that Carrie (Claire Danes) has a very important side gig in addition to her full-time job at the nonprofit agency — and Saul (Mandy Patinkin) is going to go ballistic when he finds out what it is.

In the episode, Saul pays a visit to Carrie at her new workplace and asks her point-blank whether she's acting as an adviser to President-elect Elizabeth Keane (Elizabeth Marvel). Keane is a friend of Carrie's former colleague/flame(?) Otto (Sebastian Koch), and the concerns she's expressed about U.S. military operations sound eerily similar to the concerns Carrie has had in the past, so Saul has put two and two together and come up with a theory. Initially, Carrie laughs in his face at the notion, but when Saul notes what an embarrassment it would be for everyone involved if Carrie was acting as a bug in the ear of the president-elect, she gets insulted and asks Saul to leave.

Well, as it turns out, Carrie is indeed acting as an adviser to the incoming president — who finds herself in a political pickle before even taking office, when Dar Adal (F. Murray Abraham) says he's acquired Israeli intelligence that indicates Iran is cheating on the nuclear deal. At Carrie's suggestion, Keane asks that Saul go to Abu Dhabi to investigate for himself.

Homeland continues to mirror real-life politics in Season 6

We don't know the details of how Carrie got tapped to be an advisor to the president, but on the surface, it sure looks like she's trying to absolve her own personal guilt about initiatives like the drone program by dismantling them from the inside.

The other twist in all of this is that Dar has surveillance images of Carrie getting searched before taking her meeting with the president-elect. "She's a menace," Dar tells Saul. But before he can pull out the photos as proof of their collusion, Saul assures Dar that he confronted Carrie and she gave him her word that she's not working with the incoming president. Dar never does show Saul the photos, so the question is: Does Dar believe Saul, and therefore knows that Carrie is lying to him? Or does he think that Saul is the one lying?

In other developments, Quinn (Rupert Friend), the "Man in the Basement" who gives the episode its title, is probably in the running for the worst Airbnb guest Carrie has ever had. On the first morning of their new arrangement, he starts the day by throwing a coffee mug at her head when she tries to get him to take his medication. And it's only downhill from there. After Carrie enlists Max (Maury Sterling) to babysit him, Quinn sneaks out to a bodega to buy beer and baby wipes, but then has a seizure in the store because he hasn't taken his meds.

Via Quinn's radio, we also get our first appearance of Brett O'Keefe (Jake Weber), an Alex Jones/Rush Limbaugh-type character who's loudly ranting to his listeners about "illegal black ops wars," "tainted blood" and the Zika virus — and who has evidently convinced Quinn he needs to stock up on canned food.

At the end of the day, after Max asks Quinn why he's being such an "asshole" to Carrie when she's letting him live in her house, Quinn seems to soften a bit and asks Carrie what exactly happened to him before he landed in the hospital. She discovers that he's never seen the infamous sarin gas video and shows it to him at his request, pointing out the floor tiles that eventually led her to his rescue. (We also learn that Quinn flatlined for a full three minutes in the ambulance, meaning that regardless of what his mental state is, the fact that he's even alive is a miracle.) Quinn verifies that Carrie saved him and asks her simply, "Why?" It's a genuine question, with no trace of bitterness, and all Carrie can do is ugly-cry and then apologize before leaving the room.

As for Sekou (J. Mallory McCree), Carrie and Reda (Patrick Sabongui) find out that his "friend" Sad was seeing Sekou's sister on the side, and also is a confidential informant for the FBI whose real name is Tyrone Banks Jr. A former gang member, he agreed to work with the FBI in order to avoid jail time for drug crimes he committed in Philadelphia, and has played a role in basically entrapping Sekou by encouraging him to make inflammatory videos and giving him $5,000 in cash — which the FBI is claiming Sekou wants to donate to ISIS. Sekou's now facing several years in prison, and unless Carrie can convince Sad/Tyrone to testify, things are not looking good for him.

Homeland airs Sundays at 9/8c on Showtime.

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