Labyrinth of Cinema Ending Explained [SPOILER!]

SPOILER ALERT: the following article contains massive spoilers, including the ending. If you have not yet seen the movie, proceed at your own risk, or better, come back to this article later!

SPOILERS AHEAD

Labyrinth of Cinema Plot Summary and Synopsis

Setouchi Kinema, the only movie theater on the Onomichi seafront, is about to close its doors. Its last night of existence will be an all-night marathon screening of Japanese war films. When lightning strikes the theater, three young men in the audience find themselves thrown back in time into the world inside the screen. The trio are thrust into the Boshin War, the Second Sino-Japanese War, the Battle of Okinawa and then finally Hiroshima on the eve of the atomic bombing. There, they meet the traveling theater troupe “Sakura-tai”. But can they alter the course of destiny to save the troupe?

Source: Wikipedia (CC BY-SA 3.0).