deus ex machina /ˈdejəsˌɛksˈmɑːkɪnə/ noun /ˈdejəsˌɛksˈmɑːkɪnə/
noun
Learner's definition of DEUS EX MACHINA
[singular]
: a character or thing that suddenly enters the story in a novel, play, movie, etc., and solves a problem that had previously seemed impossible to solve（小说、剧本、电影等作品中突然出现的）解围人物（或事件）