Whatever claims to obscurity she can still make will not last long after the Dec. 16 release of “Rogue One: A Star Wars Story.” In this latest chapter of the epic outer space adventure, Ms. Jones plays Jyn Erso, the scrappy and unlikely leader of a team of rebel fighters tasked with stealing the plans for the Galactic Empire’s planet-killing war machine, the Death Star. (As fans know, these are the events that precede the original “Star Wars” film, known as “A New Hope.”)
“Rogue One” could be a breakthrough opportunity for Ms. Jones, who is not usually seen swinging her fists or piloting interstellar vessels in tentpole action movies, and for the makers of the “Star Wars” series, who in recent films have featured women more prominently.
True to her own unassuming spirit, Ms. Jones played down these possibilities in a conversation, as she spoke by Skype from a patio at the Hotel Bel-Air in Los Angeles, instead emphasizing her passion for strong, relatable characters in whatever form they take.
“It’s hard to find an indie that has a great female lead — it’s hard to find anything,” Ms. Jones said.
“We wanted the audience to relate to Jyn as a person,” she added. “Like all of us, she’s trying to work out what the hell to do.”
The filmmakers and co-stars who have worked with her over the years say this is typical of Ms. Jones, who would rather keep her head down and work than look up and see where her accomplishments are taking her.
“When you meet Felicity, it doesn’t really add up,” said Gareth Edwards, the “Rogue One” director. “She’s incredibly — and I mean this in a positive way — incredibly normal. None of this, so far at least, has in any way affected her. It’s kind of remarkable.”
Born and raised in Birmingham, England, Ms. Jones said she came from a “family culture of education being prized and important, and having a balance — I wasn’t a Judy Garland-type child actress.” (She did, nonetheless, appear on TV shows like “The Worst Witch” and its sequel, “Weirdsister College.”)
Another treasured household ritual, she said, was piling in the car with her parents and brother to drive 90 minutes to the nearest multiplex and see whatever was playing; as a result, Ms. Jones grew up admiring idiosyncratic actresses like Christina Ricci in “The Addams Family” and Samantha Morton in “Morvern Callar.”
After graduating from Oxford, Ms. Jones moved to London to pursue acting full-time, appearing in stage productions at the Donmar Warehouse and getting a crucial break in a TV adaptation of “Northanger Abbey.” (“It was a fusion of studying English at university and being a fan of Jane Austen, as all English women should be,” she said wryly.)
The film that helped bring Ms. Jones to America’s attention was “Like Crazy,” the 2011 feature that cast her and Anton Yelchin as young lovers trying to maintain a trans-Atlantic relationship.
Directed by Drake Doremus from a lengthy outline rather than a traditional script, “Like Crazy” required Ms. Jones to invent large swaths of her own dialogue, including a romantic poem that her character reads to Mr. Yelchin in a tender moment on their bed.
“I’ve had people send me pictures of that poem tattooed on their bodies,” Mr. Doremus said. “It’s a tribute to her.”
“Like Crazy” has become a bittersweet bond for Ms. Jones and Mr. Doremus, who reconnected after Mr. Yelchin’s accidental death in June. “It still doesn’t quite feel real and make sense,” Mr. Doremus said. “He’s just in everything we do, and influences everything we do.”
What Mr. Doremus said has stayed with him about Ms. Jones’s performance was how she set aside self-consciousness to play such an open and vulnerable character.
“The cool thing about Felicity is she’s not an actor, she’s a person,” he said, “and there are a lot of people out there that are actors first and people second.”
Keeping those spheres of her life separate became a greater challenge after “The Theory of Everything,” in which she played Jane Hawking, the wife (now ex-wife) of the physicist Stephen Hawking (Eddie Redmayne), who cares for him as he is weakened by a motor neuron disease.
The success of the film, for which Mr. Redmayne won an Oscar and Ms. Jones was nominated, still startles her. Ms. Jones said they approached the movie no differently than they would an intimate independent feature.
“One of my favorite films is ‘Splendor in the Grass,’” she said, “and we would try to emulate those naturalistic, impassioned performances.”
She added, “When you hear the two magic words — which are, ‘It works’ — then you know something has come together.”
After the nominations and a whirlwind publicity tour — during which Ms. Jones was flying between Los Angeles and Barcelona, to make the fantasy coming-of-age drama “A Monster Calls” — she suddenly found herself being sought for some of the biggest films of her career.
Those included Ron Howard’s adaptation of “Inferno,” the Dan Brown thriller, in which she starred opposite Tom Hanks as a doctor with a more complicated agenda.
“She’s not an overt careerist,” Mr. Howard said of Ms. Jones. “She’s not a personality — she’s not trying to be a brand. Her brand is to do good work and to make her name in that way.”
She was also being considered for “Rogue One,” in a role for which Tatiana Maslany and Rooney Mara were also reportedly tested.
Mr. Redmayne — who had his own ill-fated audition for the “Star Wars” film “The Force Awakens,” then landed the J. K. Rowling franchise “Fantastic Beasts and Where to Find Them” — said he could see Ms. Jones wrestling with herself over her blockbuster opportunity.
“We did have a discussion about it — although it was probably meant to be top secret, so she probably wasn’t allowed to,” he said with a laugh.
More sincerely, Mr. Redmayne added, “It was crazy times for both of us, and you need someone to articulate the complexities, the eccentricities and the hilarities of the entire Hollywood system.”
Mr. Edwards, whose credits include “Monsters” and the 2014 remake of “Godzilla,” said that “Rogue One” deliberately reverses some of the tropes of the original “Star Wars” trilogy and the story of Luke Skywalker.
“‘A New Hope’ is the story of a boy who grows up in a tranquil home and dreams of joining a war,” he said. “What if we have the story of a girl who grows up in a war and dreams of returning to the tranquillity of home?”
To that end, Mr. Edwards said he was not looking for “an action star in the classic sense — the clichéd expectation of a soldier or a rebel.”
“You can teach anyone to fight, with enough stunt training,” he said. “But you can’t teach someone to have that soul in their eyes. Whenever you point the camera at Felicity, there’s just so much going on inside.”
The casting of women in the lead roles of fantasy films like “Rogue One,” “The Force Awakens” and “Ghostbusters” has proved unexpectedly provocative, drawing the ire of those few frustrated fans who call it a concession to political correctness.
Ms. Jones sidestepped this issue, saying that “we wanted the audience to relate to Jyn as a person, whether you’re a boy or a girl, a man or a woman.”
Kathleen Kennedy, the president of Lucasfilm, the studio that makes the “Star Wars” films, was more direct about whether she felt she had to placate these critics.
“I have a responsibility to the company that I work with,” she said. “I don’t feel that I have a responsibility to cater in some way.”
She added, “I would never just seize on saying, ‘Well, this is a franchise that’s appealed primarily to men for many, many years, and therefore I owe men something.’”
What Ms. Jones said she takes away from the “Rogue One” experience is the feeling of camaraderie that comes from inclusion in the four-decade “Star Wars” franchise. “It taps into some kind of deep mythology,” she said. “I don’t think anyone who’s been a part of it has any critical distance from it. It really takes your heart, it does.”
Perhaps more tangibly, what she has retained is her training in wushu, a style of martial arts that Jyn Urso uses in combat situations.
“We didn’t want it to be balletic and majestic,” Ms. Jones explained. “It’s all quite short, sharp movements. We wanted it to feel authentic and a little bit dirty.”
“She has this short stick, and then she grabs onto it and she just hits,” she said, beginning to swivel in her chair as she described it. “I can feel it now; I absolutely love doing it. I have to be careful not to do it on my friends or on my boyfriend or on my family.”