the game is up

​

used to tell someone that you know what their secret activities or plans are and that these cannot continue

用来告诉某人你知道他们的秘密活动或计划是什么，以终止这个活动;事已败露;戏该收场

The game is up, the teacher knows who took the keys.

秘密泄露，一切都完了，老师知道谁拿了钥匙。

Okay, you two, the game's up! Give me the cigarettes - this time I'm telling your parents.

好了，你俩，狐狸尾巴露出来了!把烟给我——这回我可要告诉你们的父母了。