This game (W.T.) is a first-person 3D escape game, an adventure game.
The stage is a mansion with walls, floors, and ceilings all without color. If you are left behind in this mansion, you need to search for an exit.
However, there are many tricks (=puzzles) in this labyrinth, and you cannot reach the exit unless you solve them.

You start the game from a room with one door.
Open the door and you should find a winding corridor and a puzzles.
You have to solve the puzzle. Because if you don't do that, even if you go ahead, you will come back to the original position.
You solve one puzzle and proceed down the corridor, but you are presented with a set of puzzles beyond that...

This version is a trial version, and you can play 2 chapters in the first half of all 5 chapters.