She looked startled by his presence, then concealed her emotions behind an impassive expression.
Since people rarely bother to think about the meaning behind a figurative expression, anything that sounds right will foot the bill.
Morgan was careful to screen his impatience behind a polite, attentive expression.
Hiding his determination behind an easy expression, Harry got to his feet.
His eyes flickered momentarily, then he retreated behind a withdrawn expression which gave absolutely nothing away.
David asked and she looked up at him with calculating eyes behind a neutral expression, made a decision and resumed her writings.
Honor hid an internal grimace behind an expression of calm attention.
Eragon's eyes widened before he caught himself and concealed his shock behind a more neutral expression.
Hiding his pleasure behind a bland expression, Ituralde turned to face the speaker, on the other side of the room.
Janeway wondered what sort of thoughts moved behind an expression like that "About what?"