fly on the wall

Definitions

A quiet, non-participating, or unseen observer; an eavesdropper or witness.

idiomatic

Equivalents

Examples

“James W. Gerard, ex-Ambassador to Germany, the first speaker of the evening, said that at that moment he would like⟳ to be a fly⟳ on the wall of the palace at Potsdam to hear⟳ what the Potsdam gang were saying about our soldiers.”

“I wish⟳ I'd been a little fly⟳ on his chamber wall when he found out that he had to go through the Michigan Child Custody Act!”

CEFR level