What is cat in a bag?

"Cat in a bag" is a phrase that is often used to refer to a situation where someone is keeping a secret or hiding something. It originates from the idea of trying to contain a cat in a bag, which can be difficult and unpredictable.

The phrase is typically used to describe a situation where someone is trying to conceal something, often something that is deceitful or dishonest. It can also be used to refer to a situation where someone is trying to keep a surprise or secret from someone else.

Overall, "cat in a bag" is a metaphor for something that is difficult to control or contain, and can have consequences if it is revealed or discovered.