opening night
noun [ C usually singular ] uk/ˈəʊ.pən.ɪŋ ˌnaɪt/ us/ˈoʊp.nɪŋ ˌnaɪt/ (UK also first night)
（戏剧、电影等的）首演之夜，首映之夜
the first night that a play, film, etc. is performed or shown
The ballet's opening night was a huge success. 这场芭蕾舞的首演之夜获得了巨大的成功。