Pick up a painting for the Hooded Wings.
Scarlett should go to the Inner City. Her goal is to enter a house and steal a painting, but to reach the door to the house, she must go through the Inner City Catacombs. There is only one entrance to the Inner City Catacombs, by swimming in a canal under a bridge not far from the Tavern. Scarlett it should enter the catacombs there. (Click on map to enlarge.)
In the Inner City Catacombs (1), Scarlett needs only to swim up to the ramp and walk up to the platform and turn left, following the platform to the end. (Dealing with any Grippers she encounters along the way.) The platform ends (2) in a ladder climbing up through a well or sewer, and that leads back to an isolated landing in the Inner City.
On the isolated landing there is a door to the house. Scarlett can enter the house using the special key Grimm gave her. (Note that there is a living gargoyle statue over the door, but unless Scarlett comes here very late in the story when she has reached high Level, it will not come to life at this time.)
Inside the house, Scarlett will find the desired painting on the wall across from the door.