noun
play within a play
Refers to a story or performance embedded inside another story or performance, common in theater, film, and literature.
この映画は劇中劇の構造をとっている。
This movie uses a play-within-a-play structure.
シェイクスピアの『ハムレット』には有名な劇中劇
Shakespeare's Hamlet contains a famous play within a play.