The series co-creator tells the story behind the trickiest props in "Bagman" and what he says is Bob Odenkirk's finest moment so far.

Deep in production on “El Camino: A Breaking Bad Story,” Vince Gilligan kept hearing about an episode of the upcoming Season 5 of “Better Call Saul.”

“We’re all in the same suite of offices and every time I would pass them in the hallway, this thing would get bigger and bigger in the telling,” Gilligan told IndieWire. “Gordon Smith and Peter Gould really tortured me because they were telling me for weeks and months in advance of reading the scripts how big it was gonna be. I’d say, ‘When am I gonna read this script you guys are cooking up for me?’ And they’d say, ‘Oh, it’s gonna be a wild one, man. It’s big!'”

Gilligan — creator of “Breaking Bad” and co-creator of “Better Call Saul” along with Gould — has returned every season to direct at least one episode of the ongoing evolution of Jimmy McGill. As promised, what became “Bagman” was a process stacked with challenges few installments in either series have had. There’s Jimmy and Mike’s trek through the desert after an ill-fated pickup of $7 million in cash. Their ensuing trek meant Cheri Montesanto and the rest of the “Better Call Saul” makeup department had to give Bob Odenkirk a sunburn and chapped lips that signaled the effects of the Albuquerque heat the crew was experiencing for themselves. The episode even crests with a truck somersaulting across the road, a cannon roll crash executed by stunt driver Corey Eubanks.

One of the centerpiece elements of the episode ended up being the ambush scene that kicks off the unplanned portion of Jimmy’s drive out to the desert. Gilligan-directed episodes have had their share of gun work before, but capturing the full spatial scope of the bloody shootout was a grueling, meticulous process that demanded everyone’s full attention.

“Directing porn is probably the same way. You think it’s gonna be really cool and then you’re like, ‘God, this gets old fast!'” Gilligan said. “There’s all these technical issues. Before every take, you gotta put on eye protection and ear protection. Half the time the gun’s gonna jam on you because the blanks don’t quite cycle the mechanism of the rifle like it should. Meanwhile, it’s over 100 degrees and we’re all scorching to death out there under the blazing sun. No exaggeration, it’s the hardest scene I’ve ever directed. It took five days to accomplish and I felt like I’d just been through the meat grinder by the end of it.”

Before the chaos of bullets commences, the moment when the episode tips over from a stickup to a standoff comes right after a visual callback that connects Jimmy’s near-death experience to characters in the expanded “Breaking Bad” world who haven’t been as lucky. Season 3 of “Breaking Bad” ends with a very similar camera angle, a POV shot of a character looking straight down the barrel of a gun.

Greg Lewis/AMC/Sony Pictures Television

“Also, in the pilot episode of ‘Breaking Bad,’ pulling back from the barrel of Walt’s pistol as he’s waiting for what turns out to be the firefighters to arrive. I guess it was a callback to both of those things,” Gilligan said. “It was just trying to put the audience in the head of this poor guy who’s about to get his brains blown out, what that must feel like looking down this enormous barrel of this gun. This thing looks so big it looks like a garage door or something.”

That wasn’t the only part of the episode with more than a passing connection to “Breaking Bad.” The desert scenes were filmed on the To’hajilee Indian Reservation, a place that might sound familiar to viewers of the other series, even if the shooting location wasn’t exactly the same.

“That’s the reservation on which Walt and Jesse first cooked way back in the pilot. Even then, the distance from there to where we shot the scenes in this episode was a solid hour’s drive. It was rugged out there. It was remote,” Gilligan said. “We thought, ‘Man, we’re gonna go through so much turmoil getting all the trucks and all the equipment out here, but at least once you’re out here, it’ll be nice and quiet.’ But this is Native American sovereign territory out there. We’re holding these poor folks up while we’re trying to fire off machine gun rounds or whatever. So there’s a balance to be struck between getting the job done, but not inconveniencing folks who live out there. We’re guests in their house, so to speak.”

With the human casualties on screen in “Bagman” confined to the nameless enemies offed by Mike’s sniper skills, maybe the most emotional death in the episode isn’t a person at all. To cover their tracks, the desert-bound pair push Jimmy’s trusty Suzuki Esteem off a cliff, crashing to the valley floor below.

“Having Jimmy say goodbye to this thing, that was kind of sad. It was bittersweet as well with the destruction of the RV that Walt and Jesse cooked in. This felt similar to that,” Gilligan said. “The good news now is that we used a photo double. The original one still exists, safe and sound in the parking lot over at Q Studios. It’s still in great shape and we can always go to a flashback of it in the future.”

Greg Lewis/AMC/Sony Pictures Television

The car wasn’t the only inanimate object that took up a significant amount of attention in the process of making the episode. With the catalyst of the entire episode being the bail money that Jimmy’s entrusted to bring back to town, the logistics of showing and transporting that cash became an involved process.

“We had many, many conversations about that. Our wonderful prop master Mark Hansen, in the earliest meetings, he brought in a great many different duffel bags and we got to pick what we wanted to use. There’s a prop company that provides photorealistic fake prop money that he has to rent from. It’s a deal just to get that stuff across state lines and all the way up from LA to Albuquerque,” Gilligan said.

To make that trudge through the desert more believable, Odenkirk wanted to have the bags filled with enough weight to make it a challenge to move them. But as Gilligan explained, there’s not a person alive who’d have been able to lug all that money — fake or otherwise — as far as Jimmy does.

“[Mark] had his crew pack it into these duffel bags. Then I tried to lift it and he said, ‘Be careful.’ Turns out each bag weighs 75 pounds. So yes, we know exactly how much $7 million dollar bills weighs in hundred dollar bills. It weighs 150 pounds. 75 times two,” Gilligan said. “A pretty healthy guy could could get it down the street, maybe, with a lot of stopping and starting. But he’s not gonna get it 20 miles through the desert.”

For all the fireworks that come before, Gilligan said he’s especially proud of the tonal balance of the episode’s final moments. With fresh water and hope dwindling down to their last drops, Mike’s last try at a motivational speech finally rouses Jimmy from his sunburnt despair. With purpose, Jimmy takes a gulp of urine from his Davis & Main water jug and follows Mike on their road back to refuge.

“That was a moment I was really nervous about. When I read the script, I said to Peter and Gordon, ‘I understand this is meant to be a very serious, very dramatic moment, but I just worry a guy drinking from a bottle of pee is gonna make people laugh. I’m just worried in the execution, something will be lost and it’ll be silly.’ And I shouldn’t worry because it all came down to Bob Odenkirk’s acting,” Gilligan said. “I think for me, that’s the finest moment. This quiet, indeed wordless moment at the end of the episode where he looks so chewed up and spit out. But he is so determined to survive at all costs and get back to the woman he loves. Then when he swigs from that bottle, it’s not the least bit funny. It’s exactly what I hoped it would be and more and that’s all due to Bob. I really do believe that’s the finest single moment of acting I’ve ever seen Bob do and that’s saying a lot. I just don’t know how he’s gonna top that.”

“Breaking Bad” Season 5 continues Monday night at 9 p.m. on AMC.

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