Have a tiger by the tail. A tiger idiom with the meaning of you are not as much in control of the situation as you thought you were. Trying to control something which turns out to be much more difficult than anticipated.

Think about holding a tiger by its tail. Technically you would be in control of the tiger. But wouldn’t you be scared that the tiger would use its strength to seize control and eat you? Of course you would – and that is the sense of this animal idiom.

Working directly with my boss is not so easy. I feel I have a tiger by the tail.

Promotion has not been easy. This department is difficult to manage. I’ve got a tiger by the tail.