If you loved Brother, try Sonatine
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.
What they share
Both films are directed by Takeshi Kitano, and they both carry the outsider mood tag, and they sit in Crime / Thriller territory. If that's the register that drew you to Brother, the second film will land in a comparable space — through a different lens.
outsider
What Sonatine is
Okinawa. Summer heat, buzzing flies. A yakuza lieutenant arrives from Tokyo, ordered to mediate a dispute. Soon ambushed, his crew retreats to the shore. Days of dangerous idleness follow. Kitano's peculiar crime film mixes violence with childish games.

