The G-Man walking around in HL2

I've noticed the G-Man walking around in various areas in HL2 and the episodes...always just outside of the normal camera range unless if you really look at him.

I realize that this is just a bit of cinematic flair and Valve is playing around here a bit, but I'm curious...is there any way to interact with him? Shoot or kill him even?

I'm currently about halfway through Episode 2 and just noticed him walking on a far-off catwalk. I didn't have access to a weapon at that point but it kind of made me wonder.

Solution 1:

No, he is never close enough to harm. He is immune to being shot, even if you reach him via noclip or other means.

Source (including list of locations)