This quest begins immediately after The Welcoming Party. After hearing about the connections that the dockmaster, Grigorii, might have with the Order, Eivor returns to the Trade Depot to investigate.
Investigate the Trade Depot
You’ll find the Trade Depot in the southeast of Jorvik, just east of the docks. When you reach it, you’ll need to enter from the roof. All the other entrances are blocked. As you enter from the roof, you’ll find guards throughout the depot on all levels. Assassinate the guard on the highest level and read the note beside them. You’ll need to kill all the guards within the depot so you can inspect each of the teal objectives unhindered. There are six guards in total, one of which is a Woe-Bringer. Shoot the fire pot beside the Woe-Bringer to bring him down quickly, and finish off the others.
Once you’ve killed all the guards, enter the southernmost room and inspect the exotic wares and the written orders. You’ll also find a bunch of minor loot in this room, alongside a wealth chest which contains the unique weapon Spinning-Death. The written orders indicated that market stalls associated with the Order of Ancients operations are marked by black cloth.
Explore Coppergate Market and the Sewers
You now need to explore Coppergate Market in search of a tall guard wielding a two-handed axe. To find them quickly, use Odin’s Sight to highlight the teal objective. When you find the correct guard, he’ll begin to speak to another one beside him. After the guards have spoken, follow them north east. You should keep your cloak on and keep your distance from the guards as you follow. When they reach the building with the black cloth, they will stop. At this point you can kill them all and loot the key from the Woe-Bringer.
Use the key to enter the building where the Woe-Bringer and the other guards stopped. Once inside, climb down the ladder to the sewers and follow the path until you reach a room containing a few more guards, and civilians. Kill the guards and loot all the silver in this area, then go through the door to the north. When you enter a cutscene will begin, during which you’ll discover that the dockmaster, Grigorii, is in fact the Needle. After the scene he will escape, and you’ll need to defeat the guards before you can pursue him.
The guards you need to defeat include a Wolf-Stormr, who is accompanied by a Rabid Wolf. These can be a deadly combination in a tight space, so be sure to leave the room by the door you entered from. This will provide you with much more space in which you can dodge the attacks of the wolf and his master, but it will also expose you to more guards. Use the environment around you to take cover, and kill the wolf first. You’ll also need to avoid the traps of the Wolf-Stormr, but this should be easier in the larger room.
Kill the Needle
When all the guards are dead, follow the teal objective marker to the west of the sewers. This will take you outside, where you’ll find Grigorii. A cutscene will begin, after which you’ll need to kill Grigorii. This will be extremely easy to do, as he only takes one or two hits to die. After the cutscene following his death, the quest will end.