the writing is on the wall | see the writing on the wall
(North American English alsothe handwriting on the wall)
(saying)used when you are describing a situation in which there are signs that something is going to have problems or that it is going to be a failure（看出）厄运临头的预兆，不祥之兆
It is amazing that not one of them saw the writing on the wall.令人吃惊的是他们就没有一个人看出大难临头的预兆。