Tom Francis Sang in 'The Mosquito Bowl' After a One-Day Notice From Pete Berg

Tom Francis learned the song he sings in Peter Berg's World War II film "The Mosquito Bowl" the night before he shot it. "Pete sent me the song and he was like, 'Just learn this for tomorrow' and I was like, 'OK, cool,'" Francis said. He assumed the scene would unfold around a campfire. Instead, Berg staged it fully, in a bar, as the last moment before the men ship off to war.

The scene has no basis in fact. David Schreiner, the man Francis plays, was not a singer in real life. Berg wrote the number in to use the actor's voice, the instrument that made his name in the West End and on Broadway.

Who does Francis play?

Francis plays Schreiner, one of four college football stars who served in the Marines during World War II. Nicholas Galitzine plays John McLaughry, Ray Nicholson plays Tony Butkovich and Bill Skarsgård plays Bob Baumann. The film adapts Buzz Bissinger's book "The Mosquito Bowl: A Game of Life and Death in World War II," about the football game the Marines played while preparing for the Battle of Okinawa. McLaughry is the only one of the four who survives the war.

Francis came to the project by design. "One of the first emails I sent to my agents was, 'This is a list of directors who I want to work with and why,'" he said. "Pete [Berg] was right at the top of the list because I love 'Friday Night Lights.'"

What does the film ask of its audience?

The battlefield sequences spare nothing. Cinematographer Jacques Jouffret set the visual rule early. "I remember Jacques said to me, 'Listen, Tom, the thing I don't want to do it romanticize this,'" Francis recalled. "He was like, 'We bought loads and loads of palm trees, but I'm not shooting the palm trees. We're setting them on fire. We can't glorify this. It has to be as true to what they went through as possible.'"

Francis called the result "visceral and intense" and admitted it is "uncomfortable at points."

The end credits give each man's age. All were 24 during the war. "They were so young. They had so much life to live. They had families they left. They had future families to make," Francis said. "I have so much respect for that generation and every generation that's come before them and after them."

What comes next for Francis?

Francis arrives in film from theater. He won a Laurence Olivier Award and earned a Tony nomination for his Broadway debut opposite Nicole Scherzinger in Jamie Lloyd's "Sunset Boulevard." Earlier stage credits include "Rent," "& Juliet" and "Hair." He made his movie debut in Noah Baumbach's "Jay Kelly" and appeared in the fifth and final season of Netflix's "You."

He wants the stage back. "I really miss the adrenaline," he said. "I really want to do a play. I want to do something original." Berg, he added, has shaped how he works: "He welcomes you into a family, and he'll be there for you whenever you need him."

"The Mosquito Bowl" is in theaters now. It debuts on Netflix on Nov. 25, giving the story of four football players who never came home its widest audience yet.