クローズドサークル

noun

closed circle (of suspects)

A term from mystery fiction referring to a situation where a group of people are isolated and one of them must be the culprit. Often used in discussions of detective novels, films, and games.

• このミステリー小しょう説せつは、吹雪ふぶきで閉とざされた山さん荘そうを舞ぶ台たいにしたクローズドサークルものです。

  This mystery novel is a closed-circle story set in a mountain lodge cut off by a blizzard.

• クローズドサークルの設せっ定ていでは、外がい部ぶからの犯はん行こうは不ふ可か能のうだ。

  In a closed-circle setup, a crime from outside is impossible.