Darkness has fallen over the galaxy far, far away.

In “Rogue One: A Star Wars Story,’’ opening nationwide on Friday, the Empire continues to strengthen its grip across space. Having infiltrated and overthrown the Republic, annihilating its Jedi knights in the process, the Empire’s fascist leaders are determined to build the Death Star, a super-weapon fearsome enough to crush any remaining resistance.

It’s in the shadow of such a threat that the Rebellion strikes back, determined to stand against the rising tide of tyranny. At the outset of “Rogue One,’’ which takes place during the latter half of the roughly 19-year period of imperial reign between “Revenge of the Sith’’ (2005) and “A New Hope’’ (1977), the rebels have charted their first concrete path of resistance: stealing blueprints for the Death Star out from under the Empire’s nose in an audacious heist. The operation is entrusted to a ragtag team, including soldier Cassian Andor (Diego Luna), warrior-monk Chirrut Îmwe (Donnie Yen), assassin Baze Malbus (Jiang Wen), droid K-2SO (Alan Tudyk), and pilot Bodhi Rook (Riz Ahmed).

At the group’s forefront is Jyn Erso, played by Felicity Jones, a tenacious vagabond brought into the fray by war vet Saw Gerrera (Forest Whitaker), and whose personal connection to the mission is key to its success.

For Jones, who spoke by phone from a San Francisco press junket, it was critical that “Rogue One’’ convey a rebellious, optimistic spirit that would carry resonance far beyond the theater.

“Ultimately, the film is about hope and self-belief,’’ she says. “It really has quite a joyous conclusion, and it is about believing in yourself and having hope. And I think that’s very important for these times.’’

Arriving in the twilight of a grim, disturbing year that saw political and civil rights protests roil America and many other parts of the world, “Rogue One’’ may turn out to hold more resonance than anyone involved could have predicted. In following a multicultural coalition that unites against political illiberality, it does much to capture the global zeitgeist.

“It’s great when a film sparks a dialogue, and obviously, “Star Wars’’ taps into so many universal themes,’’ says Jones, who was Oscar-nominated for the Stephen Hawking biopic “The Theory of Everything’’ and also starred opposite Tom Hanks in this year’s “Inferno.’’ “It’s about the path one chooses and the question of, ‘Does one become a good person or defer to the dark side?’ It brings up issues that are relevant to many people irrelevant of background or culture. It really crosses continents.’’

In the view of director Gareth Edwards, a fan of the franchise long before his “Godzilla’’ reboot convinced Lucasfilm president Kathleen Kennedy that he was the right choice to helm “Rogue One,’’ political resonance has always been intrinsic to “Star Wars.’’

“[The series] is about the human condition, about power and corruption and revolution, about good and evil,’’ Edwards explains by phone. “It’s inevitable that, if you do your job well, people will feel it’s reflecting current politics. We started this film 2½ years ago and there was no way of knowing what things would be like, but stories are cyclical and they repeat.

“If you create a timeless story, which “Star Wars’’ is, it’s always going to feel like it connects to our world. You could be showing it in 40 years and people could be asking, ‘Is it about this particular revolution, or this corrupt power system?’ We’re in the habit of going around in circles, politically. ‘Star Wars’ reflects that.’’

The franchise’s political leanings date back to early drafts of the original trilogy by creator George Lucas. A deeply allegorical filmmaker, he intended the Empire’s rise to echo that of Adolf Hitler, and for its ideology to resemble white nationalism. Stormtroopers were based, even in name, on the Nazis’ jack-booted Sturmabteilung.

Early on, “Rogue One’’ utilized history to inform its own world-building. During pre-production, Edwards and his team digitally added rebel helmets and X-Wing fighters to photos from World War II, Vietnam, and the Middle East to achieve a real-world texture.

That aesthetic carried over to filming, which Jones says was influenced by “blood, sweat, and tears’’ films like “Apocalypse Now’’ and “Saving Private Ryan.’’ The cast spent the shoot covered in mud and running from exploding bunkers.

“I loved all the grit and grime, the dirtiness of it, and the reality,’’ she says. “[The characters] are very ordinary people — they don’t have superpowers and they’re not privileged.’’

Edwards sought to convey the bleakness of life under a totalitarian regime. In one scene, the birthplace of the Force, once a shrine to the Jedi who wielded it for good, is seen to be a crumbling ruin occupied by the Empire. “During the time in which the film is set, people are losing their faith,’’ he says. “It feels like no special being is going to come and save them, so it’s up to everyday people.’’

In envisioning exactly which individuals would unite in the absence of any obvious champions, the filmmakers demanded a diverse cast.

“This is a world where you can have a giant fish and a Yeti-type character, so you’ve at least got to represent the different ethnicities of the world,’’ Edwards says of casting African-American, Latino, and Asian actors in some of the film’s key roles. “Once you open yourself to that, you can then cast anyone you want.’’

With Jyn Erso, the filmmakers looked to create a heroine with universal appeal, in the vein of Sigourney Weaver’s Ripley from “Alien.’’

“As a kid, as a guy, I wanted to be like her,’’ Edwards says of that iconic character. “It didn’t make a single difference that she was a female.’’

Jones is thrilled by the film’s representation of the Rebellion, including Jyn’s characterization as a courageous but imperfect leader. “It’s absolutely vital and it’s true to what our world is,’’ she says. “We live in a very diverse society, and it’s fantastic when film represents that. It’s in our differences that we find strength.’’

Both actress and director say that, despite its grim tone, “Rogue One’’ most strongly displays how light, intensified by the persistent bravery of an organized resistance, can triumph over darkness.

“Jyn does not give up at any point,’’ Jones says. “She goes to the very end. There’s enormous bravery in her and the other rebels — they’re all very courageous.’’

Regular human beings, distinguished only by their daring and determination, are at the heart of every rebellion, Edwards adds.

“If our film says something different to normal ‘Star Wars,’ it says that you don’t have to have special powers,’’ he explains. “If you work hard enough, and you work as a team, you can achieve nearly anything. That felt like an important message right now, to say that it’s not about being born with superhuman abilities — anyone can at any point make the world a better place. You’ve just got to decide it’s worth doing.’’

By Isaac Feldberg | Globe Correspondent

Isaac Feldberg can be reached at isaac.feldberg@globe.com, or on Twitter at @i_feldberg.