If you loved The Flu, try Asura: The City of Madness
A bridge between a film you've already seen and one most people haven't. Asura: The City of Madness has roughly 10.5× fewer votes than The Flu — it's a deeper cut, not a mainstream recommendation. 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 Kim Sung-soo, and they both carry the dread, raw mood tags, and they sit in Action / Thriller territory. If that's the register that drew you to The Flu, the second film will land in a comparable space — through a different lens.
What Asura: The City of Madness is
South Korea, present day. A wet, stained won note. Detective Han Do-kyung tries to play two sides against each other, but the mayor is monstrous and the prosecutors have their own agenda. Everyone wants something. Kim Sung-soo steers the hellish ride.

