Angry mask..? Spoiler

[Agent Aero]

So im playing through this game whilst watching a walkthrough, I'm up to the part where you solve that sliding puzzle thing and then get knocked-out and taken to that weird red house thing.

so i found the sad mask and put it onto one of them people on that torture device(?), but the video in the walkthrough showed he had an angry mask also in his inventory. I've only been watching this walkthrough since the sliding puzzle, so can anyone help me?

Thanks.