From Longman Dictionary of Contemporary Englisha flash in the pana flash in the panSUCCEED IN DOING somethinga sudden success that ends quickly and is unlikely to happen again Beene’s new novel proves he isn’t just a flash in the pan. → flash
Examples from the Corpus
a flash in the pan• I think people thought in the beginning I was going to be a flash in the pan, like Tiny Tim.• Beene's new novel proves that he isn't just a flash in the pan. 