Alicia Vikander, the Swedish actor who won an Oscar for her role in “The Danish Girl” in 2015, has taken on a remarkable range of characters in recent years – but is still stretching her boundaries, she says.

Speaking at the Karlovy Vary Film Festival, where she presented the historical drama “Firebrand” on opening night, Vikander says she’s now prepping for films that offer distinctly different challenges than her turn as Catherine Parr, the only one of Henry VIII’s six wives to outlive the marriage.

One character she admits she’s still deciphering is the central figure in the upcoming sci-fi feature “The Assessment,” a feature project with Paris-based writer/director Fleur Fortuné.

“I got the script sent to me,” says Vikander, adding that something about the story instantly intrigued her. Details are still under wraps, she says, but the film is set in a world of the near future in which the state decides who may have children. A couple is then notified that they are being considered as candidates to be parents.

Vikander, who will be half of the couple in question, according to reports, says Fortuné’s idea stood out from the stream of scripts she is usually sent.

“For Fleur it’s her first feature. But I got the script and I kind of knew. It was one of those things where I turned the page, then I met Fleur for the first Zoom.”

Vikander does her homework when considering a role, she says – “It’s like six months of my life.” What she learned about Fortuné’s work also intrigued her.

“I really had done like deep research. And she’s done a lot of short films and music videos and art work with a lot of very interesting people and she really has a clear voice. She’s really impressive.”

Fortuné, who has done wildly creative videos for Drake, Travis Scott and Skrillex, has also won over Elizabeth Olsen for “The Assessment,” which is being produced by Elizabeth Karlson and Stephen Woolley with Augenschein Filmproduktion and Number 9 Films.

“Quite instantly I just knew I wanted to work with her,” Vikander says of Fortuné. “And Lizzy Olsen, I think she’s really a terrific actress.”

While she can’t yet disclose extensive details, Vikander says, “It’s a pretty wild part. Even the producer says, like, ‘What are you going to do?’ And I said, ‘I don’t know yet.’ Which gives you a little insight.”

A key part of the appeal seems to be the challenge, says the actor, recalling how she’s shifted gears a dozen times in recent years from major action films like the 2018 “Tomb Raider” reboot to period dramas to Olivier Assayas’ HBO miniseries “Irma Vep,” about a conflicted star caught up in a dysfunctional production team trying to recreate a cult vampire classic.

“I’ve said a lot of times that I like to do parts that kind of scare me,” says Vikander. Fortuné’s concept fits the bill in that sense, she says. “I feel like I have not gone there before.”

Vikander confesses a passion for sci-fi projects such as the AI nightmare feature “Ex Machina,” which proved a breakout role for her in 2014.

“The Assessment” offers a similar dark view of where we may be going as a civilization, it seems. Vikander says it “has the sci-fi aspect in that it’s set in the close future and obviously it can bend certain rules. But when it comes down to it, it has some thriller aspects to it that I love in the genre. But it’s also quite an existential drama, with very human emotions.”

Vikander, who has husband Michael Fassbender and their toddler son with her in Karlovy Vary, says she’s in a place these days where she can be selective – and hold out for films that matter to her.

“My focus is more on the filmmakers and the people involved,” she says. “I really choose my projects based on the people I’m going to work with.”

Fassbender, whom Vikander met while filming “The Light Between Oceans” in 2016, will be onscreen opposite her again soon in writer/director Na Hong-jin’s dark fantasy “Hope,” another upcoming project.

“Besides my husband being one of my best friends, I think he’s one of the best actors of his generation. I’m super excited to work with him.”

Vikander confesses she still feels almost intimidated by Fassbender as an actor, especially when reviewing dailies of her performances. “If I’m home and sitting in our small cinema, that’s when I’m most nervous. When Michael’s going to see it.”

But Fassbender feels just as jittery about Vikander seeing his raw performances, she says with a laugh. “Obviously it’s work that we care about.”