Scary gman prank?

So I was playing gmod and I went through a door and gman’s head texture appeared in front of me, and a screaming sound played. This is not the scary gman virus. This is an E2 prank. Has anyone heard of this and can anyone explain how to do it?

I already found it.

I would recommend getting someone of your friends to explain to you in steam.

There are many ways to do this with E2.

Oh the fun that was had with the original lua script.