But then the grin faded, and he turned back to the door through which he'd entered.
Then his grin faded and all their faces turned slowly toward the north.
The grin faded when he saw the look on his friend's face.
Then his mind turned back to the murders and the grin faded.
But as he looked around, studying the room, the grin faded away.
The grin he had allowed to slip back over his face faded.
The grin faded as his thoughts went back to the letter.
The blade was moving again now, the grin having faded a little.
He looked at her and the grin faded, but only a bit.
The grin had faded by the time he got to the end.