drop in on somebody

The men and women who set the nation's interest rates don't drop in on one another very often.

"Are you sure it's all right for us to drop in on them?"

I think we ought to drop in on a friend of mine.

I thought I'd just drop in on my way and put your mind at rest.

Sounds like a bad time to drop in on the master chief.

I'd like to drop in on my daughter and surprise her.

Why don't you drop in on the school program tonight?

But he decided instead to drop in on the old man again.

And, if you're down this way again, will you drop in on me?

He left to drop in on his aunt, she said.