the bubble bursts
From Longman Dictionary of Contemporary Englishthe bubble burststhe bubble burstsDISAPPOINTEDused for saying that a very successful or happy period of time suddenly ends The bubble has finally burst in the mobile phone industry. → bubbleExamples from the Corpusthe bubble bursts• The question is, how long can this go on before the bubble bursts?• I shall not wait until the bubble bursts.