final performance; swan song; last act
Refers to the last stage appearance or final performance of a performer, group, or production. Often carries a sense of culmination or farewell.
I went to see the retiring actor's final performance.
この公演が劇団にとって最後の舞台となる。
This show will be the troupe's last act.
Compound of 最後 (last, final) + の (possessive particle) + 舞台 (stage, performance). The expression is transparent and follows standard Japanese syntax.