The Chinese idiom 一鸣惊人 (yi1 ming2 jing1 ren2) literally means amaze the world with its first song. The expression comes from a story about King Wei of the State of Qi during the Warring States Period (475-221 BC).
King Wei ascended to the throne when he was in his early 20s and as a young ruler he was not very interested in state affairs. Instead he idled away his time - playing during the day and drinking all evening. As a result, the political and economic situation in the state went downhill and several neighbouring states ceased the opportunity to invade its borders.
Some of the more patriotic court officials persuaded Chunyu Kun, a silver tongued politician, to warn the young ruler that the State of Qi was tottering on the brink. Chunyu knew the king liked stories, so one day he came to the king and recounted a story. He told the king about a bird that had perched in the same tree for many years, never fluttering its wings or uttering a sound. The king immediately grasped the moral of the story. He said:
I know the bird. Should it desire to fly, it would soar into the sky with a great flourish. Should it desire to sing, it would amaze the world with its first song.
The next morning the king took the bull by the horns. He summoned his 72 magistrates of the state to court. To reassert his authority, he honoured one magistrate for his first rate performance and executed another for his abject failure in his trusted duties. In the following months, the king personally led the royal armies to repel the invaders. After securing the state's borders, the king began to concentrate on reinvigorating the state's agricultural production. Thanks to the efforts of the king and his court, the State of Qi enjoyed many years of prosperity and power.
Today, the Chinese idiom 一鸣惊人 (yi1 ming2 jing1 ren2) is used to praise anyone who has made a success in his or her career with a single accomplishment. The English refer to this as becoming an overnight success.