The Readme doesn't exactly clarify much, so I cannot put many of my own thoughts on the Wikia as I am uncertain if they are true or not. DeeP95 was apparently an old level editor designed for use with a lot of old school games such as Doom, Quake, and Duke Nukem 3d. Due to the spelling of the first word, it is pretty easy to determine that the first word of the name comes from the level design software.
This level is inspired by "Theater" according to the Readme. Originally assuming it to be an even older Quake level, I assume now that this level is actually inspired by Duke Nukem 3d's Hollywood Holocaust and Red Light District. The starting room looks like the back stage of the stripper bar of the latter level, though with Aftershock texturing. The stripper bar itself is also visible in the level with a flashy texture replacing the Slipgate texture that has not been seen up to this point. Similar to the stripper bar of Duke 3d, there are quite a few hitscan enemies which makes the bar fight pretty lethal if you don't take proper cover.
Plenty of stuff existed in the level, though all Shells and most of the Cells have fallen out of the level. One of the Cells still remains, though oddly enough no Thunderbolt was even intended to appear in this level. A Super Nailgun also fell out of the level, though it does remain in the Deathmatch version as the conflict is removed. As the difference is non-intentional, I don't feel compelled to make a separate video for Deathmatch.
The bar itself is pretty dark and has some useless sections. There are two Shamblers in this map, making it pretty challenging as there are no decent weapons. The best way to ensure you have enough ammo is to use the Quad Damages in the stripper room to eliminate both Shamblers.
After the stripper bar is a corridor somewhat akin to the entrance door to the theater of Hollywood Holocaust, both being locked doors with a signifying exit sign (another new texture) nearby. The exit sign is halfway in the wall, making it hard to read in-game. A nearby alcove looks like the room proper from Duke 3d, even including a 25 Health like the aforementioned game. The funniest thing is that this room originally had an exploding wall, which you should recall was the feature of the previous level!
The rest of the map is pretty similar to the theater of Hollywood Holocaust. We have the main theater which is where I assume the titular name comes from, though the screen uses a sky texture which makes it unknown if it was actually intended to be a theater. An upper room accessed by a stairwell represents the projector area, even including the secret room (much easier to find behind a very visible wall, in fact the entrance to the stairwell is probably the hardest thing to find here). We also have a two doored room that could possibly represent the bathroom, though this is highly assumed. A Double-Barrelled Shotgun in this room is the only weapon that does not fall through the map.
This level, according to the author, was designed with Deathmatch as the more focused upon element even though Single Player was intended as well. If this is the case, I am quite surprised, as all the spawn points are right next to each other. Due to the limited amount of stuff remaining in the level due to most falling out on startup, I can't see really any appeal at all for Deathmatch games.
For Single Player, this level is pretty interesting. We got a semi-recognizable layout to some of the popular rooms in Duke 3d, plus we get to see a few new textures. Definitely the best looking area is the stripper bar. The limited amount of Ammo and couple Shamblers placed in the level means there could be some level of challenge. Still, I am not a big fan of the hidden nature of the wall to the stairwell, though it is akin to the darkness of Duke 3d (one of the reasons I wasn't a big fan of this game).
