You'll lower one half of a bridge going into an opening shaped like a bird’s head. Soon after this, you’ll come to a three-level room with four metal dogs and a bookcase you can raise up and down with your twirly thing.
It's the 27th scene on the 'load scene' screen (including the first that’s highlighted by default, the long descent by ladder into the underground world).
The secret room is on the right hand side of the middle level. There’s a painting in here too.
Confusing scene numbersIf you’re loading a scene from the ‘load scene’ screen on the main menu, note that I’ve counted scenes from the first that’s highlighted by default (the long descent by ladder into the underground world). There is also the prologue, but ignore that when you count the scenes. For reference:
- Scene 10 is the bright room with a big tree in the middle
- Scene 17 is the room shaped like a birds head with a stained glass window for an eye
- Scene 24 is behind a huge clock-face
- Scene 39 is the cable car
- Scene 46 is the giant broken hamster wheel