Kill the guy in the first chamber.
Run down the stairs and step towards the big door.
Push it open and enter the hall.
Kill the next guy.
Run up the two sets of stairs and kill the next guy.
Cross the bridge and turn into the passage on the right.
Run down the stairs to find a fountain and two more baddies.
Run back up and on the stairs turn around.
Get the whip out and use it to swing at the metal bar.
Jump into the alcove opposite.
Climb through the archway and turn right.
Draw the whip, take a running jump into the room and use the whip to hold on to the chandelier.
Jump into the alcove opposite.
Follow the path across the next bridge.
Walk around the edge at the wall.
You will come to a ladder.
Kill the four baddies below by using the switch to drop the chandelier onto the table.
If they did see you before that you might have to fight them in person.
Get down and collect all the weapons lying around.
Climb back up and use the whip to swing towards the chain.
Jump to the chain and hold on to it.
Turn right towards the alcove above the picture.
Jump there and climb in.
On the left by the fireplace you can pick up bottles or at the end are some chairs.
Arm yourself and then open the door on the left to meet four baddies in the billiard room.
Finish them all.
Collect the remaining weapons.
Then collect the library key on the shelf by the window.
Get out through the door.
Open the other door and run back down into the hall.
Now you can open the door on the left.

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