Royal palace investigstion mission

[MDK]

I’m at the mission that you ivestigate the palace to find who the snake is, and there is this locked chest but I don’t see a key anywhere and I checked all the other investigtion marks in that room. What am I missing? Thanks

[ClancyDamon]

Did you see the broken ladder? What do you usually do with ladders that your character do without one? What is that broken ladder right in front of? Climb the bookcase and move left across the statue to the other bookcase with the cloth. Key's up there.