Usually it was just to say hello or send news of a mutual acquaintance.
We had a few mutual acquaintances, so I heard about him here and there.
"I met her recently, at the home of a mutual acquaintance."
The man and the woman were strangers, set up by a mutual acquaintance.
A mutual acquaintance, she said, told her that he had died.
Thus far no mutual acquaintances had come to light, either.
We started off, and I knew she wanted to talk about our mutual acquaintance.
If possible, have a mutual acquaintance introduce you to him or her.
But I've got a passenger, an old mutual acquaintance, who has some real important information.
Scores of mutual acquaintances will know whom she means, anyway.