Netflix thriller 'It Has Become Night' (밤이 되었습니다): cast, rules, and where to watch

It Has Become Night (밤이 되었습니다) hit Netflix on December 4, 2023. The 12-part Korean thriller came from director Im Dae-ung and writer Kang Min-ji, adapting the web novel of the same name.

U+ Mobile TV launched it as an original, rolling it out simultaneously on Netflix and other OTT platforms. OCN picked it up for broadcast in 2024.

The six leads—Lee Jae-eun, Kim Woo-seok, Choi Ye-bin, Cha Woo-min, An Ji-ho, and Jeong So-ri—are students in class 3, year 2 at Yuil High School. They're forced into a mafia game that won't stop.

Thirty-one players enter at once. The game ends only when one side is completely wiped out, not when numbers equalize. Execution comes three ways: unanimous mafia targeting, rule-breaking, or the most votes. When it happens, severe tinnitus and headaches hit first. Once the symptoms stop, the target's eyes turn white. Then they start harming themselves.

The Doctor role is the only escape. Unlike standard mafia rules, the Doctor and Police abilities work during the day, not night, with a 48-hour cooldown between uses. Every player learns who used an ability the next morning. A Doctor-protected player blocks both mafia attacks and vote-based executions. If they're executed anyway, they revive the following morning. The mafia can eliminate two or more players at once depending on circumstances.