"밤이 되었습니다" (It Has Become Night): Cast, plot rules and platforms for the 12-part Korean thriller

It Has Become Night (밤이 되었습니다) hit U+모바일tv on December 4, 2023, landing simultaneously on Netflix and other OTT platforms. OCN picked it up for broadcast in 2024.

Directed by Im Dae-ung and written by Kang Min-ji, the 12-part series adapts a web novel of the same name. The cast includes Lee Jae-eun, Kim Woo-seok, Choi Ye-bin, Cha Woo-min, Ahn Ji-ho, and Jung So-ri.

Students from Yuil High School's second-year class 3 are forced into an endless mafia game. Thirty-one players. No quitting. The game ends only when one side is completely wiped out.

The rules break from what most players know. Police and doctor abilities activate during the day, not at night. Each ability has a 48-hour cooldown after use, and whatever gets used is disclosed to all 31 players the next day. The doctor role is especially powerful: it blocks both mafia attacks and vote-based executions. If a doctor-protected player is executed anyway, that player revives the next morning. The mafia can eliminate two or more players simultaneously depending on circumstances—a departure from the standard one-kill-per-night format.

Execution happens when a player is unanimously designated by the mafia, breaks a rule, or receives the most votes. The physical toll is brutal. Severe tinnitus and headaches hit first, then the symptoms pause and the target's eyes turn white, followed by self-harm and extreme choices.

Yuil High School itself is strange. It was once covered in media as a vocational school, but no information about it can be confirmed afterward. An insider named Heo Yul claims a female student died by suicide at Muyeong Training Center in the past. An investigation by Oh Jung-won found the facility has no operational records at all. A school and a training center that don't officially exist. Thirty-one kids stuck in a game that won't end.