[Warning: This interview contains spoilers for Wednesday's episode of FX's Fargo, "The Lord of No Mercy."]

After perhaps a slightly slow start to its third season, Fargo has been on a multi-week tear, delivering a string of episodes packed with dark humor, increasing emotional torment and mystery.

[You've been warned on the spoilers.]

This week's episode featured the season's largest twist to date, with the accidental death of sad-sack sibling Ray (Ewan McGregor), who bled out after a a shard of glass from the frame surrounding Emmit's (McGregor) priceless stamp lodged in an artery in his neck. That leaves poor Nikki Swango (Mary Elizabeth Winstead), beaten within an inch of her life last week by V.M. Varga's (David Thewlis) henchmen, all alone and, we suspect, on the verge of being a murder suspect.

The past two episodes have been helmed by Irish director Dearbhla Walsh, an Emmy winner for Little Dorrit and, of note, the first woman to direct a Fargo episode. With European-shot credits including Penny Dreadful and Amazon's recent The Collection, Walsh is only beginning to branch out shooting on this side of the Atlantic with Fargo and an episode of Netflix's upcoming Punisher series.

Walsh got on the phone to discuss Wednesday's unexpected casualty, the pleasures of shooting in Calgary, making Winstead act in an ice bath and why she gets such pleasure out of Varga's awful, awful teeth.

The full Q&A ...

From Tudors to Penny Dreadful, you've directed a lot of television that has aired stateside, but was this your first time crossing the pond, as it were, to direct episodic TV?

One other time that hasn't been aired yet, which was an episode for the new Marvel series The Punisher, which I did just before Christmas, but it's not airing until November. I directed that in New York and edited in L.A., but this was my first directing experience in lovely Canada.

The Fargo set in Calgary is like its own little world. How far out of your comfort zone was it?

It was a truly unique and virgin experience for me, I have to say, coming from the wetlands of Ireland. I've filmed around the world and I've definitely filmed in cold in climates before. I filmed The Borgias in Prague, which was quite particular, when you were doing sunny Rome with snowflakes coming through the windows of the Sistine Chapel in Prague. I found this both exotic and inspiring, both creatively and historically. It was like a tundra, the vast prairies covered in white. I just marveled at it. The first week, I just would look out the window and think about the first pilgrims who arrived and the indigenous peoples and how do you survive in such huge, vast expanses? Everything just looked so beautiful and exotic in the snow, even industrial smoke coming from chimneys and industrious freeways, the modern world and then suddenly everything looks like you put it in a snow globe. I really found this a very unique experience from a climate and landscape point of view and then to be able to translate that photographically was a joy.

And I have to say that in last week's episode, the first of the two you directed, I actually made note of how invested it seemed to be in the physical space and landscape, the little people in this vast world. Was that something you felt you were bringing with your fresh eyes beyond what was in the script?

Yeah, very consciously. Especially leading up to Nikki's beating. We all know there are the classic Fargo shots that are so exciting, like the cars that are dots on the horizon coming towards us. I shot a few of them, they're so Fargo-esque. But finding the location for Nikki's beating, I had a real picture in my head of what I wanted. I really had this sense that I wanted something that felt like it was at the end of the world and then that it would be something industrial and ugly — a beautiful ugly or an ugly beauty — and then this sense of Russia, because of course Goran's character [Yuri], his darkness is so informed by his historical experience of being an immigrant to America. I suppose as an Irish director, I find that really interesting, and how people's stories and their history, you can't escape it, you can't escape the work of your ancestors and what has happened and how you got to here, you carry it in your passion in both darkness and light. It has all of that in that writing and then coming to it as a director, the different things that you respond to, like Varga's two henchmen, one being the intellectual who reads Chekhov and the other being tech-head from Asia, it's so interesting what is it about our past that creates people of responsibility today.

You mentioned shots that are Fargo-esque and I've talked with Noah about his sense of the show's grammar, but is there a literal primer or explanation given to incoming directors for the show's visual language and what shots are Fargo shots and maybe what shots are not?

Yes and no. Noah, when he sits with you, really talks about using the camera to tell the story, not following the normal conventions of needing lots of coverage. So many shows, all people want in the end is to cut to the close-ups and see your words spoken by the actors, but he's very much about, "How can the camera tell the story?" the visual medium of it. The team on it are extraordinary. They're like a family and it's just a wonderful combination of pride in the work, loyalty to Noah and to the production and then people, I suppose, living in a part of Canada where there isn't a huge amount of [film and television] work done and then when good work comes, people are so, so committed. There is a sense, a very instinctive sense. There isn't a literal, "Oh, that's so Fargo," but sometimes you go, "Oh my gosh, that's so Fargo." Sometimes the humor or the "What now?" or sometimes it's even in the expressions, but it's almost at this stage something instinctive.

So it's not literal, as such, but the ambitions for the show are high, like Dana Gonzalez, my director of photography, this is his third season and he knows the show so well and is so interested in maintaining, but also pushing the boundaries from what's been done last year and how can we find new ways of telling the story, getting very excited when you come up with a new idea of how the camera can tell the story. And sometimes it's just the simplicity of these great performances and how powerful the script is and how sitting on a mid-shot can tell the story or finding those architectural wide shots where people move in and out of frame. He pushes you to be ambitious and not be safe, and I think that's quite an unusual position for him to take, which very exciting.

This is a show that graphically dropped an air-conditioner on a character we'd barely met, but here we are in this episode and we have the death of a character who we might have assumed could be the season's hero and it's this very understated thing. It's "Wait. THAT'S going to kill him?" How did you want to honor the importance of this death, while also keeping it this subtle?

It was very interesting, because in the way the script is structured, our mind and our focus is all the time on Nikki, that it's Nikki who's in danger. That's part of the cleverness of the script. Our eye is on Nikki. We don't, for a moment, think that Ray is in difficulty and we didn't want to signpost that in any way. If anything, we enjoy the emotional moment in episode five when she goes with him to get his wedding suit. We have the lovely moments of togetherness. They're not aware that they're kissing for the final time. It's things like that where you're just really enjoying their romance. So then when he leaves her in the motel room, we don't make a big deal of anything. We stay with her for a moment.

We storyboarded the sequence with the frame and the breaking of it in part technically because Ewan is playing both characters, and in my first storyboard I had heightened a couple of the moments, like the glass falling through the air in slo-mo. Then when I looked back on it, it was, "No, we don't need to heighten the moment." The horror of it is the shock, that it happens so quickly that we don't see it coming. There's no heightened moment. There's no self-aware or self-conscious photography around it. It just looks like it's, yet again, an exhaustive exchange between the two boys about this stamp, that we don't see the moment coming. In our minds, it's being a kid and it's two little boys with a toy and just pulling and choking, like you pull the doll or the teddy between you as a kid and suddenly the head is in one hand and the arms and legs are in the other and somebody's in tears. I think it was that situation of just trying to get that sense of two boys fighting over a toy and that, in this case, the freak accident of it, one shard of glass landing that does what it does.

It was important to Noah and important to us that we almost throw it away and then the shock is, "Oh my gosh, Ray" and the fact that we can't believe one of our heroes is going to die and then the horror on top of it is that his brother, Emmit, doesn't help him. Suddenly we move from "Oh my gosh, Ray is dying" to "Oh my gosh, Emmit is doing nothing." So our story is moving forward at such a pace and that was all quite conscious. And then we go back to Nikki, who doesn't realize that her other half has passed. So apart from the bloody horror of the freak accident of it, there's the emotional horror of it that we were looking to land the most. Then there's the final phone call to Varga, that Varga now knows that he has Emmit trapped forever, that he's called him instead of Sy. Emmit is just falling deeper and deeper into his hell.

You say "bloody horror," but even as Ray bleeds to death, it's interesting that we see so little blood. Why was that the approach you wanted to take?

I think it was a conscious decision throughout this [season] not to be so bloody and horrific as series two. Series two, I don't know what the body count was, but I remember Noah saying to me that his intention was that very few people would die in series three and that nobody would die using a handgun, that he wasn't glorifying violence in that way. I think that's the genius and black humor of episode one, somebody dying under an air-conditioning unit in the depths of winter. How black is that? And here we have our neck slit, but it's an accident, a freak accident, with this shard of glass. Obviously we researched that when that artery is punctured and there is a lot of blood. It comes out like a burst pipe, but we were very much not going for the gothic and much more the emotional horror and the tragedy. I think that's what's so powerful about this series, is the story of two brothers who loved each other and just keep missing their moments to make it right, which is obviously an age-old story. For an audience, it's very accessible, because we all can relate to wanting to murder, metaphorically or figuratively speaking, our brother or sister. Being the eldest in my family, I definitely have felt it often. That's what's very chilling about the series is that it could be you or me, much more than how it happened in series two. Not many of us are from mafioso families.

The scene with Nikki in the ice bath was such a wonderful, exposed moment, not in terms of nudity but her vulnerability and how it plays out over the scene. Did you actually plunk Mary in an ice bath for the scene?

Yes. Mary is extraordinary. They're all extraordinary. They do whatever is necessary for the story. Obviously after the horror of the beating in the previous episode, there was the carrying of the darkness of that into the next episode and how that plays out, how Ray wants revenge and just how clever Varga is being, that he has had his henchmen beat her, but leave no physical marks that can be seen above her clothes. Ewan and Mary, there's such a wonderful chemistry between Ray and Nikki, everybody loved working with them and they loved working together, there was always such a spark.

And that ice bath sequence wasn't showy, but I believe it was a single shot. Was that always the plan?

Again, it very much comes from Noah about being courageous with what can be told, finding the angle or letting something hold in the shot and showing the performances and the energy between the actors, because the actors get so excited when sometimes it is just one shot. It's like theater, making it work. Each take was always something different, but they can get totally lost within the shot and not have to worry about pickups or coverage. Added to that was the fact that it was a tiny little set. We re-created this wonderful location that we found in downtown Calgary where we couldn't actually use the real location.

I think we very consciously, in episode five and six, tried to shoot them together all the time, as in seeing them as a couple, because by the end of six we were never going to see them together again, so there's something very conscious and something pleasing about always seeing them together in the same frame, like Gloria [Carrie Coon] and Winnie [Olivia Sandoval], seeing them as a double act. So there are very conscious decisions so your own eyes are panning left and right, rather than the camera telling you where to look. So with Nikki and Ray, we were seeing them always as a unit in a two-shot, so that then when you see Nikki becoming this woman on a mission after this and you see her alone without Ray, the beauty of this series is the story that she actually falls in love with this guy who you think is a loser and that you think she's playing him, but it's a genuine love story, so the tragedy after this, that she's a woman alone without him, has all been couched by the photographic approach to them as a couple in five and six.

I've been loving the fun directors have been having with Varga and David Thewlis, just making him increasingly grotesque and terrifying. Did you enjoy your contributions to this process with the bloody teeth and with shots of him laying on the concrete floor?

It is so much fun! It's totally helped by the fact that David Thewlis is a joy and that he actually, himself, is shocked by the fun of it, like the fun we had of practicing, he said he was near-mortified with me turning up with the mug and showing him how, um, his, um, "fishing tackle" might fit in it and practicing with the teeth and then the idea of laying on the floor listening to music.

It's again kind of rooted in what we all do. We all pick at our teeth when nobody's looking. And when I'm listening to music alone in the house, I like to listen to it turned up really loudly. I had done a drama before about a deaf girl who witnesses a murder and one of the ways she used to listen to music, because she couldn't hear it, was to lay on the ground and feel the vibration of the speakers, and it was always such a beautiful image in that she was a teenager, and I loved the idea of taking that teenage image of how we listen to music from when we're teenagers in our bedrooms — wistful and listening to songs of love and "When will our lives ever be exciting?" — and thought to take that same image and idea and notion and apply it to Varga, who's such a dark character, but he still wants music to bring us to somewhere else and maybe to save us and to be the hope and the light. I loved that teenage image.

There was another scene that I did with him that he came to the set and what he wanted to be doing was going to the toilet during the set and it was just a brilliant idea. As it turned out, we didn't do it only because there was a key plot moment that we needed to hear that we wouldn't have been focused on if he was peeing in the toilet at the time.

That's the fun and Fargo allows you that fun and David is just up for whatever. It's always rooted in, "What would the character do?" We, you and I, do these things, but then when you apply them to Varga and then when David adds ... My friend, when she saw him, she said, "Oh God, I feel like he smells! Does he smell? He's always in the same coat. I feel like when I see him there's a stench." He just creeps you out. It's wonderful.

We're all very conscious about our teeth. Especially in American culture, American TV culture, one of the rules is people have to have perfect teeth. I worked on a production before where I wanted to cast a particular actress and she had a gap in her front teeth, and I thought there was so much charm to it. I won't name the production and she was the best person for the job, but the American execs weren't having any of it because the teeth were absolutely all wrong. So there's a joy in watching a character on American TV with such bad teeth and he glories in it. The other thing that's interesting with David is I'd meet with each actor before we start shooting and page-turn each scene because on a series like ours it's so fast-paced, and I met with David and we talked through all the scenes and I said, "Do you mind if we read through them?" and he said, "Oh, I couldn't read them without my teeth." He can't do any rehearsal or anything without having his teeth in. It so effects his character that he couldn't read the lines without them. I thought that was interesting that he's so into the character and the teeth and wearing the teeth effects how he feels and thinks so much. All of those things are so magical about a story and how a story comes together and all the nuances.

Finally ... Was it second unit or did you actually get to re-stage the moon landing?

Oh no, no, no! I got to do that! I got to do it on my last day. It was so much fun and we did it lots of different ways. And the actor had so much fun, although he practiced his line so many times about "One small step for mankind" and I didn't have the heart to tell him he'd never be on camera saying that line, but he'd practiced it and rehearsed it and he had it so perfectly. The most important thing was how you jump and how you walk, so he walked in slow motion like literally moonwalking and then I'd give him the cue and he'd bounce around. He was so thrilled. It was so much fun. We were on our last day and we had a crazy, crazy day doing all of those epic one-shotters. I definitely felt I was part of history and I personally landed Neil Armstrong on the moon, so that was a great way to feel as a director.