If you loved ST: Aka to Shiro no Sôsa File the Movie, try Kaiji: The Ultimate Gambler
A bridge between a film you've already seen and one most people haven't. Here's what they share, and what the second one does that the first one doesn't.
You already loved

ST: Aka to Shiro no Sôsa File the Movie
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Kaiji: The Ultimate Gambler
What they share
Both films are directed by Tōya Satō, and they sit in Drama / Thriller territory. If that's the register that drew you to ST: Aka to Shiro no Sôsa File the Movie, the second film will land in a comparable space — through a different lens.
What Kaiji: The Ultimate Gambler is
Tokyo streets at dusk, neon lights reflecting off a whiskey glass, debt collector's knock. A young man's desperate choices: 10 years of debt or one night on a gambling boat. Tōya Satō directs this dark thriller.