"Theatre" was developed after "Curses" and before "Anchorhead", and has many elements in common with both of these games, including some shared puzzles. It is a large, sprawling game, with many puzzles in the find-an-object-use-an-object category.
I found it slightly easier and slightly smaller than the other two games, but it may have just felt smaller because I always felt drawn forward to complete the game. A series of lost journal pages for collection provide a fascinating backstory.
As others have said, the writing feels a little off at times; however, the game gave me quite a few genuinely creepy moments during exploration, similar to the famous (Spoiler - click to show) "you forgot to close the front door" moment in Anchorhead. The game was strangely compelling despite the weaker writing.
As I said, the puzzles are slightly easier than many similar games. I also noticed that the author favored certain puzzles; for instance, there were at least five puzzles where the solution involved (Spoiler - click to show)pushing or moving a large object around.
A couple of times in the game, I thought I had put myself in an unwinnable situation by entering an area without some object I needed to get out. However, I found I was wrong. I don't think there is really any way to lock yourself out of winning, except by using one-use items when you shouldn't (when you have used a one-use item correctly, it will be obvious).
A couple of things, I wasn't quite sure what they did: (Spoiler - click to show)turning the switch in the electrical panel, and wearing the amulet. Also, as other reviewers noted, there were quite a few plot points never resolved.
However, I didn't feel cheated.
The one star off is for the lack of polish and the plotholes. Overall, though this is one of the most enjoyable games I have every played (for reference, the other games I've most enjoyed are Curses, Anchorhead, and Not Just An Ordinary Ballerina). I anticipate playing through it again several times in the future.
(I added the star back later)