Just what the Adventurers' Club is is a bit difficult to explain. It's an odd comedy club-bar-Disney show-approaching British comedy show hybrid. Having said that, it is a LOT of fun if you go into it knowing it is supposed to be zany and stupid. The main room with the atrium (wher eyou were) has two alcoves that have mini-shows. There are plaques on the wall explaining when they are. I have seen the mask room show. I haven't seen the other one.
In the main room are 5-6 shows a night. Each ranges depending on who is "hosting" and they are each quite unique. "Hoopla" is the ending show each night where everything is a bit crazy. They have a lot of audience participation and some zany songs. The room has a big stage with an organ that has "crashed" through the floor along with various other items. It is a lot of fun to look around and see the items gathered from "adventures."
It is a thing that must be seen to be understood.