In the Spring and Autumn Period (chūn qiū 春秋时期,770-476 BC), King Jing of the State of Jin (Jìn guó 晋国) fell ill. One night he dreamed that the disease turned into two small figures talking beside him. One said, ‘I’m afraid the doctor will hurt us.’ The other said, ‘Do not worry. We can hide above huang and below gao. Then the doctor will be able to do nothing to us.’ The next day, having examined the king, the doctor said, ‘Your disease is incurable, I am afraid, Your Majesty. It’ above huang and below gao, where no medicine can reach.’
The idiom indicates a hopeless condition.