。
She didn't show up.
Literal
She [topic-は] figure [object-を] did-not-reveal.
姿を現す is the affirmative counterpart of 姿を消す — 'to appear, show oneself, make an appearance,' literally 'reveal one's figure.' The negation 現さなかった makes it 'did not appear / didn't show up.' Compare also with 姿を見せる ('show up, appear'), nearly synonymous but slightly more colloquial. All three idioms (現す, 見せる, 消す) treat 姿 as a thing one can act upon — a poetic Japanese conceit where one's visible form is treated as separable from the self.