暗転

1. Origins, structure, and basic meaning

• Structure: 暗転 (あんてん) is a noun that also forms a する verb for a stage blackout or a sudden turn for the worse.
• Basic usage: It appears when a stage goes dark between scenes or smooth negotiations suddenly deteriorate.
  • 舞台が暗転すると次の場面が始まった。 — The next scene began when the stage went dark.
  • 順調だった交渉は一つの発言で暗転した。 — A single remark suddenly turned the smooth negotiations sour.

2. Common pitfalls and similar expressions

• Stage lighting and worsening circumstances
  • 暗転 can describe a stage literally going dark or figuratively mark a favorable situation suddenly worsening.