POV is "Manning" and the whole point of the paragraph is just to highlight that the guy ("Cannon") just has the look of a cold-blooded killer. This scene is taking place in an interrogation room, just as Cannon is allowed to enter alone while Manning is sitting there. Can you help me improve this? Cannon’s eyes were the deep blue color of frostbite, unblinking and unmoving in their appraisal. They bore into him with cold, unblinking menace. Like the hunter in a lion’s den, Manning could feel very acutely that he was in an enclosed room with an exceptionally dangerous man.
There's a lot redundancy here, and you're doing a bit of telling instead of showing. Cannon’s eyes were the deep blue of winter ice; his unblinking gaze seemed to bore into Manning's very soul. Manning felt a chill run down his spine and he broke eye contact first, cursing himself for showing weakness before this man.
Instead of "Manning felt a chill run down his spine," why not just say "A chill ran down Manning's spine."
