in the dark

to be in a position where you don’t have a lot of information

Example Sentences:

A: Do you know where Mark is?
B: No, I’m in the dark right now. I haven’t seen him for one week.

We were in the dark when the power went out, and we couldn’t find out why.

Media and Links:

Boomers leave kids in the dark about their wealth

Similar idioms:

1. take a stab in the dark
2. health is wealth
3. hit the road