This page details how to complete the Hidden quest in the Siege of Paris DLC, leading you to three Books of Knowledge and the legendary one-handed sword known as Joyeuse.

How to Begin the Hidden Quest in Francia¶

To begin the process of searching for any trace of the Hidden Ones in Francia, you’ll need to read a note in the form of an Agent Report. You’ll find this note in most major settlements throughout Francia, but the first place you’ll come across it as at the longhouse in Melun. As you approach the throne from the western entrance to the longhouse, use Odin’s Sight to highlight the note just in front of the central fire. Once you’ve read it, the Hidden quest will automatically begin.

The Agent Report details the following:

“My brother,

I scouted the ruins west of the slums of Paris as you asked. Within I found an ancient door bearing a symbol much like the letter A yet strangely altered. Perhaps you know it? The door would not open. While I struggled with it I caught movement just beyond the edge of my sight. A careful search of the area revealed nothing, yet I cannot banish from my mind the image of a hooded figure.

The area may already be in use. I think we must search elsewhere for our new camp site.

Vive le rebellion.

–P“

Where to Find the Hidden Ones Bureau in Paris¶

As you probably guessed, the note indicates that a Hidden Ones Bureau is likely to be found in Paris, just west of the slums. The entrance to the bureau can be found at the centre of some Roman ruins. As you approach the entrance (a hole in the ground), you’ll discover that the bureau has a name: Lutetia Bureau. You’ll find it easy enough to make it to the entrance of the bureau, but the door is locked and there is no other way inside. Once you’ve read the note on the body in front of the entrance, the quest will update and you’ll be tasked with finding three keys to open the door, each one found at three separate ruins:

• Champlieu Ruins
• Diodurum Ruins
• Gisacum Ruins

These ruins are located across the map in Francia, each of them offering a new special ability along with the key. We’ll begin with Champlieu Ruins, which is located to the northeast of Paris.

How to Find the Champlieu Ruins Key¶

As you approach the location of Champlieu Ruins northeast of Paris, use your raven to scout the area and locate the entrance to the ruins. You’ll see a breakable wooden barrier with some dead guards around it. Shoot through the barrier and then drop down the hole to find a Hidden Ones door, which can only be opened by your Hidden Blade. Interact with the door to open it, then continue to the barricade at the southern side of the hall.

To reach the Book of Knowledge, pull the barricade toward you (northward) until it passes the hole in the wall to your right (west). You can now go through the hole in the wall further north on the western wall, dispersing the rats with melee attacks as you go, until they’re all inside the sewer grate. You can now loot the nearby pots and then slide under the hole in the wall to reach the Book of Knowledge, which provides the Goule Breath special ability.

Once you’ve looted the Book of Knowledge, slide back under the hole in the wall and take one of the fire pots. You may need to disperse the rats again first, since they’ll cause the fire pot to explode if they reach you while you’re holding it. If this happens don’t worry too much, as the fire pot will respawn. Take the fire pot back to the main hallway and use it to destroy the stone barricaded wall on the eastern side of the ruins. Beyond here you’ll find a hidden room containing the Champlieu Key.

How to Find the Diodurum Ruins Key¶

When you reach the Diodurum Ruins (located west of Paris) and use your raven to scout it, you’ll see a breakable wooden barrier near the centre of the ruins. You won’t actually find an entrance through here, so don’t bother exploring it. Instead, go to the pond located east of the ruins, just beneath the cliff, and enter through the cave on the northern side of the pond. As you swim through you’ll eventually reach a point where you’ll need to dive under the water to proceed. You can then climb up to reach another door which can only be opened with your Hidden Blade.

Interact with the door to open it, then jump down the hole on the other side, into the water below. Swim northward, then west, then south, until you’re able to resurface in a room with some fire pots and a breakable wall. Use one of the fire pots to destroy the wall, then proceed into the room with the Book of Knowledge, which provides the Golden Flame ability, and the Diodurum Key on the table at the northern wall.

Once you have both the Book of Knowledge and the key, you can exit the Diodurum Ruins from the same way you entered, or by moving the barricades beyond the door to the south.

How to Find the Gisacum Ruins Key¶

The Gisacum Ruins are slightly different than the other two ruins, since you’ll need to avoid or kill some Frankish soldiers to get inside. As you approach the ruins, use your raven to scout them and look for the breakable wooden barrier on the ground. You can destroy this and then jump down the hole to another door which can only be opened with your Hidden Blade. You should be able to avoid the nearby Frankish soldiers relatively easily, but there aren’t too many to be concerned about if you’d rather kill them.

Once you’ve interacted with the bureau door, go inside and run to the left (western wall) to find a wealth chest containing a Tungsten Ingot. You can then run to the right side of the room (eastern wall) to find the Gisacum Key in the corner. If you’re not bothered about getting the Book of Knowledge further up, you can leave at this point and return to the bureau in Paris. However, if you want the Plague of Rats special ability, you can take a fire pot from the western wall and use it to destroy the breakable barricade at the northern wall. Through here you’ll find another breakable barricade which can be destroyed with a fire pot or the Incendiary Powder Trap special ability. You’ll find the Book of Knowledge in the rubble beyond this wall.

Explore the Lutetia Bureau in Paris for the Joyeuse Sword¶

Now that you have all three keys from the - Champlieu, Diodurum, and Gisacum Ruins, you can use them to open the door at the Lutetia Bureau in Paris. When you enter this bureau you’ll find that it’s much larger than the previous three, but you’ll be looking for one piece of treasure in particular to complete the quest: the Joyeuse one-handed sword.

As you first enter the bureau you’ll be able to explore the room to your west without being harassed by rats. Here you’ll find a note which details the abandonment of the bureau, in much the same way that those in England were abandoned. When you’re ready, jump down into the main chamber of the bureau and use your torch to light up the ground. You’ll find markings here in the form of the Hidden Ones symbol, pointing toward the southeastern wall. You can destroy the barricade blocking the way down to the treasure by using one of the fire pots which can be found on the level above the main chamber, or by using the Incendiary Powder Trap special ability.

Once you’ve destroyed the wall, you’ll need to kill a number of snakes which surround the wealth chest. You can then loot it for the Joyeuse one-handed sword. At this point the quest will update, indicating that you should leave the bureau. As you do, you’ll notice the symbol on the ground is now lit by flames. Before you leave, take the opal at the northwestern side of the chamber, then climb up to the exit. When you reach the quest marker Eivor will comment on some footsteps, suggesting that they’re not alone. A note will be left near the door, which you can read to complete the quest.