When casting the role of Sam for his film “Gunpowder Milkshake,” which hits Netflix July 14, co-writer/director Navot Papushado knew he had a tall order to fill. The role of the deadly assassin required a bona fide movie star, someone who could carry an entire film and appear in almost every scene. She had to have action skills to be able to execute elaborate fight choreography often done in one long take without a double. And not just traditional action scenes — we’re talking some of the most inventive fights committed to film in recent memory, including a sequence where Sam can’t move her arms on her own so she has weapons strapped to her hands while using the rest of her body to propel their movement. She also had to possess some real dramatic chops, as Sam shares deeply emotional scenes with the eight-year-old girl she rescues and she risks everything to protect. Oh, and she had to be funny, as the movie never takes itself too seriously and is an adrenaline-fueled blast that will have you gasping and laughing in the same breath.

So it’s really no surprise Papushado landed on Karen Gillan, the Scottish actor and filmmaker who has already excelled in genres from sci-fi (“Doctor Who”), horror (“Oculus”), comedy (“The Big Short”) and action blockbusters (the “Guardians of the Galaxy” and “Jumanji” franchises.)

“Karen is the perfect Sam,” Papushado says. “I can’t think of anyone else for the role but her. She has such unique qualities and range. She can be funny, intense, dangerous and vulnerable, all at the same time. She loves to explore and try new ideas and approaches.”

It also helps that Gillan is “one of the nicest, most down-to-earth people I have ever met.” “She was fully committed from the get-go, and always with such a positive and generous energy. She brought so much of herself to the role, and her insights helped shape the script and the movie,” Papushado says. “She also embraced the tough, physical aspect of the role and all the training for the action scenes. Because of her commitment, we were able to add more elements and ideas to the action than we initially planned.”

For her part, Gillan was drawn to the role the moment she read the script by Papushado and Ehud Lavski, which was written in a style that captured how the unique action scenes would play out. When told how pleasantly surprised it was that the movie was more than just a solid action film, elevated with humor and heart, Gillan admits she had the same reaction.

“Just the title caught my attention, because, like, that’s a cool title!” Gillan admits with a laugh. “And I’m reading and thinking it’s a good action film, sort of like your initial response.” And then she got to the aforementioned sequence with the paralyzed arms. “And that’s when I ran to my agents. I was like, ‘You have to get me in this film.’ It’s just like nothing I’ve ever read before. The audience won’t know whether to laugh or cry. They won’t know what to do, but they will know they’ve never seen anything like this before. That’s so cool and ballsy.”

Gillan jokes that she’s gotten this initial response before where people seem surprised how good a movie is — few people expected the “Jumanji” reboot to be so fantastic and “Guardians” initially entered the Marvel world with less brand awareness than other superheroes. “It’s funny — I’ve done several films where people use the word ‘actually’ when they’re describing how good it is,” she says. “They’ll be like: ‘It’s actually really great!’”

Of course, Gillan herself is part of the reason many of these films are elevated beyond the norm — her performances always involve real stakes no matter how outlandish the premise, from Sam to the surly yet sympathetic Nebula in the Marvel films. “I approach the action genre as seriously as someone would approach their big dramatic showcase role — just really making the most of it,” Gillan notes. “Even though it’s very stylized and heightened in this film, the character is living it.”

As for the humor often threaded in her roles? “I think that’s just a natural instinct. I grew up watching a lot of American comedy and that’s ingrained in me.”

In “Gunpowder Milkshake,” Sam is abandoned by her assassin mother, played by Lena Headey, at a young age. One of the first things Gillan told Papushado was that she wanted to explore the abandonment issues in the film. “It sounded so serious for such a popcorn movie,” Gillan laughs. “And I was like, ‘Don’t worry, I’m going to make this fun! I just need to know for myself for the character.”

Papushado actually appreciated Gillan’s deep dive into the character – in discussing the fight scene where her arms are immobile, he points out that it’s complicated because of both the physical and mental state Sam is in. “She is outnumbered, outgunned and the stakes are now much higher because there’s a little girl she needs to protect,” he says. “Karen and the stunt team trained like crazy to make sure we nail the physical elements of the scene. But more than anything else, it’s Sam’s attitude that really shines through. She’s now a caged animal fighting for survival. With nothing left to lose, Sam leaves elegance behind and becomes wild and vicious. There are so many moving parts to that scene and keeping the physical rules while selling the craziness of it all was the biggest challenge. I can’t think of anyone else besides Karen that could’ve nailed it like that.”

Though she’s left by her mother, Sam does have the great fortune to grow up with a trio of “aunties” played by no less than Angela Bassett, Carla Gugino and Michelle Yeoh. “I had to deal with being starstruck for the entire movie,” Gillan laughs. “Which is actually hard when you’re that starstruck and supposed to be playing a cool character in front of these people.”

Gillan says she’s often fanning out — how could she not be — but nothing compares to when her “Guardians” character Nebula joined up with the superheroes in “Avengers: Infinity War” for the first time. “That was pretty wild sitting with all the Avengers. They were all in costume and just sitting around chatting and I was like, ‘I’m sorry. This is not normal. Like, what?’”

Gillan actually entered the Marvel world as more of a casual fan when she was first cast. “I’d seen the ‘Iron Man’ films and thought they were really good, but hadn’t really seen the other ones,” she recalls. “Then I caught up for research, started reading the comics and really got sucked into the world, and I get it now!”

Gillan has already shot her role as Nebula in the upcoming “Thor: Love and Thunder” for director Taika Waititi, and while she obviously can’t say much, she has nothing but raves for the filmmaker. “Taika is amazing. It was so cool to take this character and work with him. Taika definitely brings out a different, more silly sight of Nebula, for sure. Which makes total sense because his stuff is more wacky and bonkers, in the best possible way,” she notes. “His technique is so improvisational, especially in a big blockbuster film, you don’t expect to get that much freedom to improvise. He just shouts out things like, ‘Do this! Say that again! Again!’ It’s such a fun experience.”

She will return to Nebula again for director James Gunn, who she refers to as “The OG,” who first cast her in “Guardians of the Galaxy” in 2014 and is set to direct “Guardians of the Galaxy 3” later this year. She credits Gunn with exploring a more emotional side of Nebula, noting, “He was really keen on making her this well-rounded character.”

And yes, Gillan has read the script, and will only say: “It’s incredible.”

Up next, Gillan has already shot roles in Judd Apatow’s “The Bubble” and Riley Stearns’ “Dual,” about a woman who makes a clone of herself. After pointing out that this isn’t the first time she’ll be acting opposite herself on screen, Gillan laughs and notes, “It’s the strangest kind of typecasting I’ve heard of.”

She’s also written another feature, “Axe Wound,” which she hopes to direct, which would make her sophomore feature following her 2018 debut “The Party’s Just Beginning.” It’s a full circle moment for the actor who says she spent her childhood running around with a camera and making little horror films in her house. She still remembers one vividly in which, “I played a school girl by day and by night, I put on a blonde wig and took a knife out and killed people. At the end, I reveal my identity as the killer to my father and then killed him.”

Still, she says she never expected to actually become a filmmaker or an action star. “I didn’t anticipate this life at all — I did not even think it was an option,” she says. “It just didn’t seem like something I would ever get to do. And here I am, in many an action movie!”


Full disclosure: Gillan starred in the 2015 short film “Warning Labels,” written by this article’s author.