Deep into the finale of Better Call Saul’s fifth season, Kim Wexler raises the idea of ruining someone’s life. Her target, the smarmy but reformed attorney Howard Hamlin, has long been stuck in her craw. “What if Howard does something terrible?” she wonders from under the sheets in the luxury hotel suite where she and her husband are holed up. Initially, he’s happy to play along. But after discussing several hypothetical scenarios, the lawyer formerly known as Jimmy McGill realizes that his wife isn’t playing at all.

“Kim, doing this, it’s not you, OK?” he says to her over a bowl of room-service ice cream. “You would not be OK with it.” Her reply is as cold as her sundae: “Wouldn’t I?”

The camera then cuts from a close-up of Kim to a nearly teary-eyed Jimmy, then back to her. “She had taken him by surprise,” says Peter Gould, who directed and also cowrote the episode with Ariel Levine. “He’s really uneasy with the direction she seems to be taking.”

“Kim,” Jimmy—or is it Saul now?—says softly, “you’re shitting me, right?” On her way to the bathroom she wheels around, pulls two imaginary pistols out of their imaginary holsters, fires twice, and pretends to blow away puffs of smoke. The only thing Jimmy can do is stare at her and force a laugh. “He’s looking at me trying to figure out, ‘Who is this person that I thought I knew?’” says Rhea Seehorn, who plays Kim.

“She fights it much more confidently and completely than Jimmy does,” Bob Odenkirk, the Breaking Bad spinoff’s star, says about Kim’s duplicitous urges. “But because she has that capacity it’s not even that strange to her, in a way.” In other words, he adds, “They’re more similar than when you first meet them and you think they’re not at all.”

For Jimmy McGill, whose livelihood depends on a certain moral flexibility, this is a shocking epiphany. His wife has spent the entire series as both a guide to and a guise of integrity—keeping him from fully accepting a life of indecency while also providing him evidence that he could be decent. But “Something Unforgivable” is a point of no return; it’s the moment Jimmy realizes that Kim Wexler is just like him. Or worse: just like Saul Goodman.

By the fifth season, Jimmy has grown comfortable in Saul Goodman’s colorful suits. The latest installment of Better Call Saul reckons less with its main character’s transformation, than with the potential for osmosis.

Because Better Call Saul is a prequel, the fates of most of the show’s major characters are predetermined. And while there’s plenty to learn about Saul Goodman before he meets a certain former chemistry teacher, or about Gustavo Fring before he sits atop a drug empire, as a matter of fact, no Better Call Saul character is as mysterious as Kim. And knowing that, the show’s cocreators, Gould and Vince Gilligan, have wisely taken their time unveiling her true nature, reaching sublime heights by drilling deep into the character and letting her descent—and Jimmy’s role in it—unfold in a painfully deliberate manner.

“The show, it’s called Better Call Saul,” Odenkirk says. “But the real show is, Who the Hell is Kim?”

It’d be easy to blame Kim Wexler’s slow-building deceitfulness on her slippery partner. But Seehorn rejects that theory. “It isn’t as simple as saying, ‘Jimmy is turning her bad,’” Seehorn says. “That’s not correct. So is he reigniting something that was always there? Is he bringing it out in her?”

At the outset of Season 5, Kim seems, at best, conflicted. She vocally objects to Jimmy’s decision to practice law as Saul Goodman, yet in the premiere, “Magic Man,” she takes a page from his playbook and lies to a stubborn client so that he’ll take a favorable plea deal. After the deception, she rushes into a stairwell, throws her briefcase down, and almost collapses from shame.

Still, her affection for Jimmy remains. After his license is reinstated, she buys him a new leather monogrammed briefcase—the initials JMM, not SG—and a travel mug playfully emblazoned with the phrase “World’s 2nd Best Lawyer.” Naturally, the yellow cup pops up later, when Kim opens Jimmy’s bag and finds it—pierced with a bullet hole.

“Every detail is thought about, is considered, and is not forgotten,” Odenkirk says. “It must be extremely hard to write this. I just see the amount of concentration and care that the writers put in. It’s so apparent. I think the fun thing is when they surprise themselves; when there’s a detail that they didn’t even have a reason for and then they discover a reason for it.”

“The show, it’s called Better Call Saul. But the real show is, Who the Hell is Kim?” — Bob Odenkirk

Whether Jimmy and Kim are eating takeout, watching classic movies, or brushing their teeth, their routines illustrate just how close they are. Sometimes words aren’t even necessary to demonstrate their bond. In the closing minutes of Episode 3, when Kim comes home demoralized after failing to convince a man to leave his home to make way for Mesa Verde bank’s call center, she joins Jimmy on their apartment’s balcony. As they share a cigarette and drink beer, she decides to throw a bottle toward the parking lot; Jimmy follows suit. Soon, neighbors’ lights flicker on, and a dog starts barking as the two culprits smile and scurry inside. “I love all those scenes,” Seehorn says. “To me they’re more intimate than sex scenes.”

The question, however—one that’s hummed through the entirety of Better Call Saul—persists in the fifth season: What does Kim see in Jimmy? Seehorn believes the answer lies in the humble roots of her character, who grew up in Nebraska, where—we learn in a flashback this season—she was raised by a mother with alcohol misuse issues. “I’ve been delighted to see it realized in little places here and there, this real disdain for people that don’t make their own way, that she doesn’t feel pick themselves up by their bootstraps,” Seehorn says. “I see her get really pricked when she’s around people like that. It has always let me get another avenue to understand her connection to Jimmy, because he’s a hustler. You can have a problem with the result, but that guy does his own work.”

To Kim, Kevin Wachtell, the CEO of Mesa Verde, which his father founded, is one of those people who hasn’t made his own way. When he refuses to give in to Everett Acker, the blue-collar homeowner who the bank is attempting to evict, Kim turns on him. But to do so, she needs an accomplice, and Saul Goodman is the perfect man for the job.

During the season’s fourth episode, while watching Jimmy’s alter ego perform in court for the first time—he sleazily swaps out his defendant with a look-alike to prove that a convenience store cashier may have identified the wrong robber—Kim makes eye contact with him and they exchange a nod. “She’s trying to figure out, number one, who this person, this third party in my relationship, is,” Seehorn says. “But also she’s considering asking him to help with Acker, and she’s trying to gauge: Is this the guy I always smiled at when he made the billboard and did all those stunts against Hamlin? It’s not exactly illegal, but it’s definitely not playing the game [right]. Is that what she’s looking for?”

Enlisting Saul Goodman to represent Acker is the kind of clever, dirty trick that Jimmy would’ve devised. But this time it’s Kim who sets things in motion, consequences be damned. The move, intended to seek justice for the little guy, backfires. Kim tries to remove herself from the case by citing a conflict of interest, but Kevin won’t have it. When her boss Rich Schweikart (played with an understated warmheartedness by Dennis Boutsikaris) later tries to take Kim off Mesa Verde, she lashes out at him. Meanwhile, as he helps delay Acker’s removal, Jimmy begins amassing dirt on Wachtell.

“It isn’t as simple as saying, ‘Jimmy is turning her bad.’ That’s not correct. So is he reigniting something that was always there? Is he bringing it out in her?” — Rhea Seehorn

In the end, both Acker and the bank appear to be receiving favorable deals. But Jimmy, as he’s wont to do, blackmails Kevin at the last minute with dirt dug up by a hired goon. Kim has no idea the extortion attempt is coming, and in the last scene of Episode 6, aptly titled “Wexler v. Goodman,” she confronts him. As he’s apologizing and defending himself, claiming that her genuine anger successfully erased any suspicion that the two were in cahoots, she rolls up her sleeves.

“She’s so contained, but you can see underneath that containment, she’s sizzling,” Gould says.

“She suppresses and forces things into being project oriented,” Seehorn says. “We all know those people in our lives. ‘I don’t want to emotionally talk about what’s wrong. Just tell me how to fix it.’”

In this case, though, she lets Jimmy have it, calling him out for his constant stream of lies and for making her “the sucker.” “This has to end,” she says. “I cannot keep living like this. Jimmy, you know this has to change. If you don’t see it, I don’t know what to say, because we’re at a breaking point.”

Even now when he watches the episode, which Thomas Schnauz wrote and Michael Morris directed, Gould feels like Jimmy and Kim are about to break up. “These two people seem to be on very different paths,” he says. “And he’s pushed her to the limit.”

Then, as Jimmy is on the verge of breaking down, Kim agonizingly gets the last word. “Either we end this now, and enjoy the time we had and go our separate ways,” she says. “Or, we … ” Then she trails off, stammers a bit as she’s working through something in her head, and says, “Or maybe … maybe we get married.”

“Her head says one thing and her heart says something else,” Gould says. “And I think if you were to ask her, the character, ‘Well, why are you getting married?’ she would say, ‘Because Jimmy told me that he lies so he can protect me from having to testify against him.’ Which is a very lawyerly reason. But I think they get married because they love each other. And there’s some beautiful symmetry on the show, that I find fun—these are two people who got a law office for love and got married for business.”

The twist is both believable and shocking because of the dichotomy of Seehorn’s performance—the expression of genuine anger being overtaken by a calculating mind set on solving a complex problem. “She wasn’t planning on saying that, that’s why you didn’t see it coming,” she says. “So that’s what makes the moment great and that’s what makes that moment difficult.”

“You see a lot of thinking going on on Kim’s face in that moment,” Odenkirk says. “And a hesitancy to say this strange, on the surface, hard to grasp, solution to their quandary. But you see all that thinking and when you hear her say it, you just know that she means it. And you know there’s probably even a good reason that she came up with it. She has something in her mind about why that is a good choice. Which is a wonderful piece of acting on her part. I mean, just great.”

Even before Better Call Saul began, one thing was certain: Jimmy McGill could not be saved. But knowing the once-small-time con man’s destiny hasn’t made it easier to witness as it unfolds. Better Call Saul is brimming with dramatic irony—knowing the end point makes the journey all the more gut-wrenching. By the back half of Season 5, that journey is nearly complete—Jimmy has gone from small schemes to arguing for the release of Lalo Salamanca, a member of the drug cartel who’s charged with murder.

“In front of the victim’s family, he makes this argument for releasing someone who he knows, in his heart, is a murderer,” Gould says. “An evil person, Lalo Salamanca. And yet he does it. And you can argue he had no choice but I believe he did have a choice. And Jimmy feels terrible. Terrible is probably too small a word.”

After the courtroom scene, there’s an eerie shot of the newly eloped criminal lawyer slowly emerging from behind a wall. Only half of his face peeks out, but the mirrored surface of the wall creates an optical illusion, at once making the split in Jimmy’s soul clear, but also obscuring the fact that he’s hiding from the family of Lalo’s victim.

Despite the bravado that Saul projects, the transformation from mere con man to violent criminal accomplice has battered his conscience. That soon becomes apparent when Jimmy runs into Howard Hamlin, the last person on earth he wants to see. The nattily dressed lawyer, and former partner of Jimmy’s late brother, Chuck, began the show as one of its least sympathetic characters. But after struggling to cope with Chuck’s death by suicide, he’s grown into something rare for the Breaking Bad universe: someone who, over time, evolves into a better person, not a worse one.

Howard’s kindness induces a childish fury in Jimmy. Instead of accepting Howard’s offer to join Hamlin, Hamlin & McGill, he tortures Howard with a pair of nasty pranks. The reason for this, Odenkirk thinks, is simple: Howard is a stand-in for his brother. Before his death, Chuck made sure to tell Jimmy that in truth, he never mattered much to him. “What do you do with that if somebody dumps that in your lap?” Odenkirk says. “It’s awful hard to get around. In a very wacky, psychological compartmentalization, he’s decided that Howard was a part of this. It’s almost like a kid who’s gonna get bullied decides to be the biggest bully and to torture a kid who’s a different kid. Because he just knows those knives are coming for him if he doesn’t point them in another direction.”

So when Howard catches up with him at the courthouse, Jimmy becomes unhinged. In the final scene of the Alison Tatlock–penned “JMM,” executive producer Melissa Bernstein’s directorial debut, he verbally attacks Hamlin. “You know why I didn’t take the job? ’Cause It’s too small!” Jimmy shouts as he jumps up and down. “I don’t care about it. It’s nothing to me. It’s a bacterium.”

“There’s that wonderful shot where they’re trailing my face, seeing him behind me, and it flips for about three seconds and we see Jimmy,” says Patrick Fabian, who plays Howard. “He’s moving like a puppet—physically moving like something that’s possessed. And it’s not natural. It’s not human.”

Even after arranging for the release of a cold-blooded murderer, Jimmy’s job is far from over. As Salamanca/Fring double agent Nacho Varga reminds him earlier this season, when it comes to doing business with the cartel, “Once you’re in, you’re in.” So when Lalo needs $7 million in cash bail, he sends Jimmy to fetch it at the Mexican border.

“Jonathan Banks’s character, it’s like every word he says costs him money.” — Peter Gould

For the makers of Better Call Saul, this was the perfect excuse to revisit to the New Mexico desert. “I just don’t think any of us get tired of seeing that landscape,” Gould says. “You would drive through and there would be wild horses running in the distance. It is a remarkable, spiritual place. In addition to being a very difficult place to try to do a television show.”

Gilligan directed “Bagman,” an ultraviolent, bleakly comedic episode of TV that takes on the form of a Western. Written by Gordon Smith, the episode was filmed in To’hajiilee, the same expanse of Navajo land where both Walter White and Jesse Pinkman cook meth in the Breaking Bad pilot and where Heisenberg crumbles to the ground in “Ozymandias.” The shoot, which was two hours away from the show’s Albuquerque home base, took nearly three weeks.

“As the crow flies, it might not have been that far, but driving time, because of the washboard roads with all the trucks, was probably an additional hour from where we would shoot the Breaking Bad To’hajiilee stuff,” Gilligan says. “It was like going to a whole different place.”

The heat was practically unbearable. “I was bitching in some interviews about how hard it was to shoot it,” Gilligan says. “But the truth is, I had the easy job. The hard job was done by the crew, who had to schlep all that stuff out there, 50 miles out in the desert. So I had it easy.”

“It was 100 degrees every day. Up to 110,” says Jonathan Banks, who plays Mike Ehrmantraut. “And it’ll take a toll on you. And I’d give Vince a hard time every time I could. ‘What have you done to us? Where are we?’ Truth be told, I really enjoyed it.”

Early in the episode, things go awry for Jimmy. After picking up two duffel bags full of money from the twin Salamanca cousins, he notices a pack of vehicles trailing his Suzuki Esteem. Heavily armed henchmen take the loot, but as one is about to put a bullet in Jimmy’s head, gunfire rains down from an unseen shooter, sending the lawyer ducking for cover. We see much of the brutal sequence from Jimmy’s perspective.

“If you had ever been exposed to that kind of death and grisly mayhem, a normal human being would be in shock,” Banks says. “And I thought Bobby just was impressive in what he did. It got my attention.”

Jimmy doesn’t know it until he comes down to check on him, but it’s Mike who saved his life. From there, the duo heads toward civilization on foot as a surviving bad guy hunts them, eventually hunkering down at a makeshift camp as day turns to night. There, under the muted light of a glow stick, Jimmy slips and admits that Kim knows what he was supposed to be doing at the border. The ramifications of that revelation are clear to Mike. “She’s in the game now,” he says, flatly, but with a hint of disappointment.

Almost immediately confirming Mike’s bleak analysis, Kim is shown in an interrogation room with Lalo, having claimed to be his lawyer in a drastic attempt to locate Jimmy. If this season has a breakout star, it’s Tony Dalton, the Mexican TV star who plays Lalo as the drug trade’s most happy-go-lucky psychopath. “They’re all very intense characters,” Dalton says. “Especially the ones who are villains.” His goal, he adds, was to “take down the intensity. He can still be bad. He’s still gonna do all the bad things he’s gotta do. But he’s a little more carefree.”

“He’s so likable until he’s not,” adds Gilligan.

Gould credits casting directors Sherry Thomas and Sharon Bialy for suggesting Dalton for the role. “We gave them all these requirements—the charm, and the joy, and the threat,” he says. “I remember Tony, he self-taped an audition. He was holding an iPhone in front of a bookcase. Even under those circumstances, you could just see, Well, this guy is incredible. He has all the charm of a ’40s movie star.”

In the jailhouse scene, Seehorn imagined that Kim was working on no sleep. The first shot focuses on her nervously staring out the barred window, taking in a gulp of air. “Some people were like, ‘Kim is so smart, why the hell would she do that?’” Seehorn says, before answering the question herself. “You’re honestly talking about someone who is your only connection—[someone] that you love—is dying right now in the desert somewhere, or will die any moment, if you don’t do something. She can’t call the police. What would she tell them?”

“I don’t mean to wax too philosophically, but all of us, those decisions we make, we make them. And there will be a price for them to pay.” — Jonathan Banks

While attempting to extract any information about Jimmy’s whereabouts from Lalo, Kim manages to keep it together. But Dalton almost didn’t. That day, he remembers dust from set construction irritating his eyes. “I kept blinking,” he says. “Vince said, ‘Stop blinking so much, man! You’ve gotta just stare at her.’ But when they tell you to stop blinking, you really want to blink a hell of a lot more.”

During the tête-à-tête, Dalton was testing out his own intimidation techniques. “He kept reaching out those unclad toes in his sandals further and further under the desk towards me,” Seehorn says. “We didn’t talk about it when we were playing it but later I said, ‘You fucking did that on purpose!’ And he’s like, ‘Oh yes, I did.’ You can’t even see it on camera but it was driving me nuts. As Kim I was like, ‘Do not put those Vienna sausages on me.’”

Lalo refuses to divulge where Jimmy is, but predicts that he’s probably alive. “He’s like the cucaracha,” Lalo says, running his fingertips across the table like insect legs. “You know? Born survivor.”

Soon we’re back in the desert with Jimmy and Mike, who are severely dehydrated, sunburned, and exhausted. Labi Siffre’s “I Got The … ”—the track from which the sample in Eminem’s “My Name Is” originates—fittingly plays in the background: “Just a lonely soul,” Siffre sings, “Slowly dyin’ … ” Then, as Jimmy picks up loose cash that’s fallen through a hole in a duffel bag, he accidentally steps on a cactus.

“The way we discussed in the writers’ room was that he got a needle into his hand and I recall it was Vince’s pitch to have him get it in the foot for two excellent reasons,” Gould says. “One was that we didn’t want to have to do a piece of makeup—a prosthetic—on Bob’s hand that would have to run for the rest of the season.” The second reason? “Vince was able to come up with the amazing shot where he pulls the needle out.”

Post needle extraction, with a white T-shirt tied around his head and a handful of $100 bills scattered across his blood-splattered chest, Jimmy announces that he’s ready for death. “I’m gonna die in this dirt one way or the other,” he says from the desert floor. “Let’s get it over with.”

Mike isn’t exactly the type to just let Jimmy die. Though to make matters worse, Jimmy is out of water. What he does have is his own urine in a water bottle stamped with the logo of Davis & Main, the firm that Jimmy got fired from in Season 2 after—among several other silly acts of purposeful self-sabotage—not flushing the toilet. “What’s the point?” Jimmy asks Mike. “So they can find a corpse with a mouth full of piss?”

The exchange is crushing and hilarious. “Jimmy has gotten them into another fine mess and the mess just keeps getting messier and worse,” says Odenkirk, who compares Jimmy and Mike’s dynamic in “Bagman” to Walt and Jesse’s Laurel and Hardy–esque relationship in parts of Breaking Bad. “You can sweat it out with them, but another thing you can do is just choose to laugh at the degree of horribleness that continues to rise.”

What finally motivates Jimmy to persevere are the words of his stoic, sniper rifle–toting, superhuman companion. Even though usually, Jonathan Banks’s character’s unique teeth-gritting stare is enough for him to convey what’s on his mind. “It’s like he’s got a hold of some gristle and he’s gonna chomp that shit down and spit it out in your face,” Odenkirk says. “It’s fuckin’ beautiful.”

“That glare tells you what you’re worth to him,” says Giancarlo Esposito, who plays Gus Fring. “It tells you what he thinks of you. It tells you where you stand.”

“His character,” Gould says, “it’s like every word he says costs him money.”

But when Jimmy asks Mike why he’s still going, he says something that would’ve been worthy of inclusion on Friday Night Lights:

“I have people waiting for me. They don’t know what I do. They’re protected. But I do what I do so they can have a better life. And if I live or if I die, it really doesn’t make a difference to me as long as they have what they need. So when it’s my time to go, I will go knowing I did everything I could for them. Now you ask me how I keep going. That’s how.”

Banks, who chalks up his signature look to being “kind of old and bitter,” says that he enjoyed delivering the impromptu inspirational speech. And it works on Jimmy, who immediately summons enough desperation to use himself as bait to lure in the man hunting them so that Mike can pick him off. “It does motivate him to think about the people who might be waiting for him,” Odenkirk says. “In fact, the person.”

To Odenkirk, the quick-thinking courage Jimmy shows foreshadows a version of him that we’ve seen already. In the Season 5–opening flash-forward, Jimmy is in Omaha living undercover as Cinnabon employee Gene Takovic. When a cab driver recognizes him as Saul Goodman, Jimmy rushes to a pay phone to call the Breaking Bad universe’s relocation specialist, Ed Galbraith (the late Robert Forster, in one of his last onscreen roles). But before committing to Ed’s services, Jimmy hangs up and decides to take care of the problem himself.

“He does have a spirit in him that is a fighting spirit, that is an angry one, that gets backed into a corner, backed into a corner, hiding, hiding, ducking, and dodging, and lying, and manipulating,” Odenkirk says. “Really pushed into a corner until it says, ‘Fuck it. Fuck you. I’m gonna come at you with everything I got.’”

But a fighting spirit is no match for trauma. Not long after Jimmy returns from the desert, the loud, staccato sounds made by the juicer Kim is using cause him to suffer PTSD-like symptoms. Midway through Episode 9, he meets Mike in his car to talk about what happened. Having faced a staggering amount of trauma himself, Mike’s the only one who can really know what Jimmy’s facing. In that moment, he becomes a de facto therapist.

“One day, one day you’re gonna wake up, brush your teeth, go about your business, and sooner or later, you’re gonna realize you haven’t thought about it,” Mike tells Jimmy. “None of it. That’s the moment you realize you can forget. When you know that’s possible, it all gets easier.”

Mike is trying to help, but to Jimmy, it’s no consolation. “The reality is, it’s not going to end,” Banks says. “You’ve got skin in the game. And you’ve chosen your way. It’s what Mike’s done. When Mike turns and says to his daughter-in-law, ‘I’m gonna play the cards I was dealt,’ it’s a decision. And I don’t mean to wax too philosophically, but all of us, those decisions we make, we make them. And there will be a price for them to pay.”

That’s never clearer than in the season’s last two installments. Jimmy is in the game now. And so is Kim—which means there’s a good chance that she, like her husband, can’t be saved.

If the main question of Season 5 is Who the hell is Kim?, then we finally know the answer. And that’s devastating. Wracked with guilt during the finale, Jimmy asks Kim, “Am I bad for you?” When she replies that he’s crossed a line and says, “You’re not gonna do it again,” all he can muster in response is a feeble “Yeah.”

Both of them know that he’s lying. Once you’re in, you’re all the way in. And by the end of the episode, Kim’s resistance has been replaced with acceptance. “In some ways,” Gould adds, “the shoe is on the other foot.”

Everything in Better Call Saul happens for a reason. The ephemera of the show is beyond symbolic; actions and reactions linger in the shadows, waiting for the most devastating moment to leap back to the forefront of its characters’—and its audience’s—minds. In the last scene of Better Call Saul’s fourth season, Jimmy’s admission that his contrition during his reinstatement hearing was all an act causes the joy to drain from Kim’s face, as she realizes who he really is. Seemingly impervious to the profound deflation of his partner, Jimmy smiles, points both index fingers at her, and lies: “It’s all good, man.”

Kim’s finger-gun salute in the Season 5 finale is so disturbing not only because it’s something that Jimmy would do—it’s something he’s already done.