SPOILER ALERT: Do not read if you have not seen the Feb. 19 episode of “Homeland,” “Casus Belli.”

After last week’s explosive ending, this episode sets lays another few miles of twisty-turning track for the conspiracy that has been unfolding from across the street from Carrie’s Brooklyn townhouse.

The title of the episode, “Casus Belli,” refers to a provocation that starts a war — the assassination of the Archduke, as it were. What we see this week is the fallout of our key constituencies turning on a dime onto a war footing, no one more so than the deeply traumatized Peter Quinn.

President-elect Keane is whisked away from her hotel and at least temporarily disarmed — from her phone, her staff, even her ability to watch TV — as the national security industrial complex fires up all of its lockdown protocols

But the most remarkable aspect of this episode — written by Chip Johannessen and directed by Alex Graves — is not so much how the plot around Carrie thickens but the depth of the love story that is emerging around Carrie and her high-maintenance house guest. “A huge misunderstanding” is not how most parents would react to the news that their kid is being held in a basement with a man equipped with high-powered weapons.

Carrie’s faith in Quinn’s essential goodness is unwavering, even when it appears to everyone on the outside that he’s taken Carrie’s daughter Franny and nanny hostage in her basement. Carrie knows in her bones that Quinn’s only mission is to protect Franny — he will never deliberately harm her. And clearly Carrie has complex feelings for Quinn. She wasn’t exaggerating when she told him through the window that seeing Quinn bond with Franny provided “the best feeling I’ve had in a really long time.”

Quinn’s tactical instincts for surviving a targeted assault are still rock solid. But he seems to have lost the ability to size up the political realities of the threat Carrie faces. The people outside her building are all uniformly evil in his view — the overzealous news media, the protestors, the police SWAT team. Carrie, however, is still good. She undoubtedly saves his life by tackling him as the police move in and he does not fight her. “Don’t hurt him,” she screams even as she goes to comfort her daughter.

Meanwhile, Carrie also realizes that while Quinn may be a little too far over the wrong side of the paranoia line, he’s not wrong. The revelation that somebody other than her old friend got her that compromising recording of FBI agent Ray Conlin that allowed her to get Sekou released from prison (just in time for him to get blown up the next day) sets her wheels turning. By the end of the episode, after she finds the photos from Quinn’s own surveillance efforts, a grim-faced Carrie watches the shadows and light across the street.

So much of this episode unfolds in the dark — the movement and the sounds of what you can only barely make out in the shadows adds to the tension. Kudos to director Graves and to star Claire Danes for allowing Carrie’s face to show the wear and tear of enduring the worst day a working mom could imagine. No glamour shots in this episode. 

The President-elect, meanwhile, finds herself in the weirdly disconnected environment of a “safe house” estate in some remote location where the matron of the house apparently likes to watch far right-wing TV commentators. Keane has been told she has to wait for a TV set, yet when she walks upstairs she finds an Alex Jones type bellowing invective against her, against “global treaties and cooperation” and against refugees. The fact that these things are in the real-life ether today is another example of “Homeland’s” particular genius.

Other highlights of “Casus Belli”:

  • The image of Franny watching non-stop news coverage of the aftermath of the terror attack. Fear is burned into her consciousness, like most post 9/11 kids.
  • Franny’s observation about her mother being in the eye of a media frenzy was sharper than anything dished out by President Trump last week: “Why are all those people mad at her?”
  • After the trauma in the bathroom, once again Franny is handed to another couple for safe keeping. There was something ominous in Carrie’s wave as nanny Laticia and her husband (boyfriend?) drive away.
  • Dar Adal’s grudging respect for the depth of Saul Berenson’s commitment when he’s informed that the trip to his sister’s house in the West Bank was a ruse to have a meeting with their Iranian operative Majid Javadi. Unlike Dar, Saul is completely upfront with him about everything, including his suspicion that Mossad coached the Iranian agent Nafisi before Saul’s interrogation. “The whole thing was a charade?” Dar asks. “Awaiting confirmation,” Saul replies. But we’re left wondering if Dar may have been in on the charade at Saul’s expense.
  • “I feel like a deserter,” President-elect Keane says as she’s hustled into a helicopter. Dar Adal makes a point of telling Keane about Carrie’s involvement with Sekou. Will that shake her confidence in the reform agenda that Carrie has helped set?
  • “A huge misunderstanding” is also an apt description of the circumstances, as far as we know, around the explosion of Sekou’s delivery van. He’s not a jihadist, despite his YouTube screeds, but the victim of forces who turned him into collateral damage to add the fuel of fear to the national security industrial complex. After watching this episode, I found myself wondering about the motivations of Keane’s chief of staff, Rob Emmons. Just a hunch.