After its premiere last year at TIFF, Jungleland arrived in theaters on November 6 and is also available on VOD. It's a tale of two brothers, a bare-knuckle boxer named Lion (Jack O'Connell) and his manager brother Stanley (Charlie Hunnam), whose professional and personal desires clash.

O’Connell spoke to Screen Rant about how his own life prepared him for the physical requirements of the role, and how he connected to his character’s emotional trajectory.

The first question I have for you is: who is Lion Kaminski?

Jack O'Connell: Good question, man. Lion Kaminski is a brainchild of Max Winkler and Ted Bressman, our writer. He's an introverted, tough, very talented fighter. He has everything it takes to make it, but the lottery of birth hasn't been kind to him.

When you first got the script, what were your feelings about it and what drew you into the project?

Jack O'Connell: I just thought it was a story that we're familiar with. Timing played a factor. It just felt like we've sort of seeing this trajectory, because it's so common within the world that it's set, but not for some time.

Maybe bringing a story like this out now, between two males are in a very masculine environment in its purest form, was appealing to me. To kind of just focus on these two dudes who are growing up in one of the wealthiest countries on earth, but having to take part in these bare knuckle contests in order to get on, and in order to live and enjoy life.

You get to throw hands a bit with Charlie Hunnam, who plays your brother. How long was your training process, and how much time did you put into that?

Jack O'Connell: Oh, man. I took this job on because I've been boxing for ages, and I thought it'd be a good opportunity to look like I've transformed for a role - when, really, I probably did a lot of the work throughout my teens for this. So, depending how you cut it, I've probably been preparing for this role for 20 years.

And it shows! This project offers an actor like yourself a unique opportunity to be both violently physical, and to have moments of great drama and tenderness. Which scenes did you find most taxing?

Jack O'Connell: Well, it wasn't any of the physical stuff, because I enjoy that. Taxing, I want to say there's a scene just before we were set to do the final fight.

What was great about this whole procedure was that we used the script a lot, but there was definitely an opportunity to try and invent stuff at the time and see where the story was taking us. Which is great, man. It's such a great way to work. So, yeah, the scene prior to the main fight with myself and Charlie - we just burst into tears.

I like to cry; I don't find crying taxing. But there was definitely emotion to it, and it was great. It was quite cathartic. We'd shot enough of the story to have some real references, which were appropriate and true to the moment instead of trying to make yourself cry because your character should be. I just started to look at him, and it brought on this emotion. I think, in my mind, it sits well within the story at that time.

But I don't think that's a fair answer to the question. I think maybe it gets taxing when you're shooting six days a week, because of just the onslaught of scenes we were doing. That was f***ing taxing.

Jungleland Charlie Hunnam Jack O'Connell

Bare knuckle brawling is another level of finding and danger, even on set. How often did you actually get hit, or was anyone hurt on set?

Jack O'Connell: Yeah, I took a couple of digs. I did take a couple of digs, and I actually landed one in particular, in the final fight scene with a guy who's actually about to become Pro. So, I was profusely apologetic, because we still had more to do that day as well. I was profusely apologetic, and he was a gentleman about it, but I think he did catch me one in return. That's probably because he's a fighter; you don't give to not receive.

Jungleland balances on the relationship between two brothers, and this growing family that emerges. Can you talk to me about their bond and how it might be challenged?

Jack O'Connell: Well, essentially, you got this younger brother working out that he's probably better off alone. You've got this dynamic between older and younger sibling, where the older figure feels like he's a driving force in Lion's prosperity in his career. And there's probably a paternal thing going on from Stanley, because he's this replacement father, which is quite viable and respectable.

But I think the film takes place at an interesting time in their dynamic, where Lion is finding the adult version of himself. And this introverted character - which is probably a result of his older brother's extroverted nature, because he couldn't get a word in - eventually finds that his inner strength is more reliable and more prosperous. What Charlie plays with Stanley is a projected extroverted strength, because he's trying to survive using his younger brother's gift. He said in the film, if it wasn't for his brother, he'd be a professional boxer - a potentially lucrative career. So, it's a really interesting point in their dynamic.

I think the film for me is about this shift between Lion and Stanley, where Lion realizes, "I'm actually I'm actually alright without you. It's you that needs support." And I think it's handled well. I think that by the end of the film, you see the sacrifice made by the older brother in order to let his younger brother flourish.

One of the more fascinating relationships we see unfold is between Lion and Sky. Can you talk to me about that relationship?

Jack O'Connell: Yeah, it starts off as an unlikely thing between them. They're complete strangers from not all two dissimilar worlds; their backgrounds are very far removed but the world that they find themselves in is the same.

I think there's just such a mystery with Sky. You think you've got a hold of her and an understanding of who she is, and then you don't. And I think that makes Lion quite hopeless with trying to understand her. She gets him; she sees right through him, and I think for the first time genuinely wants him to succeed for nothing in return. We see in the film, and particularly the game that Lion's in, there's obviously always ulterior motives - right down to his relationship with his brother.

But for the first time, nothing is expected in return. He's just able to accept himself, because he's been accepted by Sky. He doesn't know if he's a monster or not; he's named after a wild animal, which is top of the food chain. He's asking himself, "Am I even human?" Then you have Sky bringing out very potent human emotions in him, and I think that then feeds into his ability to understand his relationship with his brother more.

Speaking of your brother, you guys have great chemistry in this film. In what ways did he push you as a performer, and what were your most memorable scenes with him?

Jack O'Connell: I think anytime where we made each other laugh. I loved the scene where we were all at Sky's house at the dinner table, and he's reeling off this skit, portraying himself as something that he clearly isn't in order to seem respectable at a typical family dinner table. That just cracked me up.

The most memorable scenes where the times where we had a laugh. I think it was very encouraging, making this film together. That's true throughout, in his relationship with Max and with Jessica; he is a real collaborator. He was totally available and just wanted to make sense of it for himself and with other people. You can't really ask for more.

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Jungleland is now in theaters and VOD.