hawk-eyed

How could he sit before the hawk-eyed man whom he was about to meet without in some way betraying his secret?

In contrast with the clean, hard, hawk-eyed miners, he looked blotched and unwholesome.

He was hawk-eyed, square-built, very red-faced, with an eye anything but expressive of saintly life.

I have observed, in doing business with lawyers, that they are exceedingly hawk-eyed, and jealous of everybody.

It behooved the voyager to observe a sleepless caution and a hawk-eyed vigilance.