Walk down the stairs, unlock some doors and enter a secret base/laboratory or whatever it is. The last part of the game is probably one of the best moments of free gaming.
But I won’t tell you what it is. Just find the control room and unlock places where you can collect some important items and have some spooky moments. The game is almost perfect but you may get a bit lost and bored when trying to find your way into the next room. However the story and background will be explained in fine narration and overall the audio is great creating fine atmosphere.