It’s a surreal moment in an already surreal war: the grave but calming baritone of actor Mark Hamill, Luke Skywalker of “Star Wars,” urging people to take cover whenever Russia unleashes another aerial bombardment on Ukraine.

The intrusion of Hollywood science-fiction fantasy into the grim daily realities of war in Ukraine is a consequence of Hamill’s decision to lend his famous voice to “Air Alert” — a downloadable app linked to Ukraine’s air defense system. When air raid sirens start howling, the app also warns Ukrainians that Russian missiles, bombs and deadly exploding drones may be incoming.

“Don’t be careless,” Hamill’s voice advises. “Your overconfidence is your weakness.”

The actor says he’s admired — from afar, in California — how Ukraine has “shown such resilience … under such terrible circumstances.” Its fight against the Russian invasion, now in its second year, reminds him of the “Star Wars” saga, he says — of plucky rebels battling and ultimately defeating a vast, murderous empire. Voicing over the English-language version of the air-raid app and giving it his “Star Wars” touch was his way of helping out.

“A fairy tale about good versus evil is resonant with what’s going on in Ukraine,” Hamill said in an interview with The Associated Press. “The Ukrainian people rallying to the cause and responding so heroically … It’s impossible not to be inspired by how they’ve weathered this storm.”

When the dangers from the skies pass, Hamill announces via the app that “the air alert is over.” He then signs off with an uplifting: “May the Force be with you.”

Hamill is also raising funds to buy reconnaissance drones for Ukrainian forces on the front lines. He autographed “Star Wars”-themed posters that are being raffled off.

“Here I sit in the comfort of my own home when in Ukraine there are power outages and food shortages and people are really suffering,” he said. “It motivates me to do as much as I can.”

Although the app also has a Ukrainian-language setting, voiced by a woman, some Ukrainians prefer to have Hamill breaking the bad news that yet another Russian bombardment might be imminent.

On the worst days, sirens and the app sound every few hours, day and night. Some turn out to be false alarms. But many others are real — and often deadly.

Bohdan Zvonyk, a 24-year-old app user who lives in the repeatedly struck western city of Lviv, says he chose Hamill’s voiceover rather than the Ukrainian setting because he is trying to improve his English. He’s a “Star Wars” fan, too.

“Besides,” he said, “we could use a little bit of the power that Hamill wishes us.”

After one alert, Zvonyk was riding a trolley bus when Hamill’s voice rang out from his phone. He said the man in front “turned to me and said, smiling: ‘Oh, those damn Sith,'” to describe Russian forces. The Sith are the malevolent enemies of the do-gooding Jedi.

Olena Yeremina, a 38-year-old business manager in the capital, Kyiv, said Hamill’s “May the Force be with you” signoff at first made her laugh. Now its enduring humor gives her strength.

“It’s a very cool phrase for this situation,” she said. “I wouldn’t say that I feel like a Ukrainian Jedi, but sometimes this phrase reminds me to straighten my shoulders and keep working.”

Sometimes it can be wise to shut Hamill off. Yeremina forgot to do that on a trip outside Ukraine — to Berlin — and paid for the error when the alarm started shrieking at 6 a.m. and, again, when she rode the subway in the German capital. She wasn’t alone. Another person in the subway car also had the app and it erupted, too. The two of them first cursed, but then “it made both me and that person smile,” Yeremina recalled.

Ajax Systems, a Ukrainian security systems manufacturer that co-developed the app, hopes Hamill’s star power will encourage people outside Ukraine to download it — so they get a taste of the angst heaped on Ukrainians by nerve-shredding alarms and airborne death and destruction.

“With Mark’s approach, it won’t be so terrifying,” said Valentine Hrytsenko, the chief marketing officer at Ajax. “But they will understand somehow the context.”

In the invasion’s first year, air-raid alarms sounded more than 19,000 times across the country, so “of course people are getting tired,” he said. The app has been downloaded more than 14 million times. Hrytsenko is among those who use its English-language setting to hear Hamill’s voice.

“For Star Wars fans, it sounds really fantastic,” he said. “It’s kind of a Ukrainian mentality to find some humor even in the bad situation or to try to be positive.”

Hamill is pleased that the sci-fi saga is again transporting people, even if just temporarily, to its galaxy far, far away.

“It does inspire people,” he said. “Everyone flashes back to being 6 years old again. And if the movie can help people get through hard times, so much the better.”