This is a guide to finding your way into the secret room in the Northcrest Manor in Chapter 6 A Man Apart in Thief 2014.
Find a Way into the Secret Room
To find a way into the secret room go to the second floor of the Northcrest Manor. Look for the golden painting decorated with lions and open the door.
Opening the Safe
Inside the right column can be lined up by peaking through a hole in the back of the table:
The left column needs the red parts facing outwards. Turn the bottom until the safe opens: