When she sat back, her face was an unreadable mask.

His face was bleak for a split second before it closed over into an unreadable mask.

The young woman stood behind him, her face an unreadable mask.

Max was quiet for a long time, his face set in that unreadable mask she hated.

There was a pause; all of the faces were turned toward him, unreadable beneath the cloth masks.

She still sat there, the unreadable mask staring at him.

She spoke in a low, neutral tone, and kept her face, still turned to the mob, an unreadable mask.

He looked down at her, his face an unreadable mask.

The Guard officer saluted and left, his face an unreadable mask.

Gabbie's face was an unreadable mask as she finished the letter.