Hidden One’s questline starts midway through the main story of ‘Seige of Paris’ DLC. Your first objective will be to look for the signs for the Hidden Ones in the Roman Ruins west of the Paris Slums. This will lead you to Lutetia Bureau (See pictures below for the location). This article shows the location of the Lutetia Bureau, how to get inside Lutetia Bureau, the Location of Hidden One’s Keys, and how to get to the Gear Chest containing Legendary Joyeuse Sword in Lutetia Bureau.
Also Read: The Siege of Paris All Collectibles & Achievements
How to Enter Lutetia Bureau
Lutetia Bureau is in the southwest portion of Paris at the location shown in the picture below. At the highlighted location you will find a big hole on the ground (See Second Picture Below). Drop down the opening to reach the Bureau. Proceed in the linear path to reach a locked door (See Third Picture Below). You will need to find 3 Hidden One’s keys to be able to unlock the door and enter the Hidden Ones’ Bureau.
Key 1: Melunois
The first key is in Diodurum Ruins in Melunois. From the fast travel point at Diodurum Ruins, jump into the water below.
In the water, you will see an entrance to the ruins. Swim through the entrance and then dive down to keep moving forward. On the other side, you will find a door with the Hidden Ones’ symbol on it.
Open the locked door using your hidden blade and enter the next room. In this room, you will see a few explosives behind some iron bars. You have to reach the location of the explosive. Jump down the water, go right, then go left and then take the next left. Here you will find your path blocked. Dive down to move forward and reach the area with the explosives. Pick up an explosive and then turn around and break the stone wall with it. Behind the wall, you will find the key kept on a table. Collecting the key also completes ‘Roman Excavation Mystery‘.
Key 2: Amienois
The second key is in Champlieu Ruins in Amienois. Go to the location marked with a yellow arrow in the picture below. At the marked location, you will find some wooden planks covering a hole in the ground, Break the planks and jump down the hole.
Down the hole, you will find a door with the Hidden One’s symbol on it. Open the locked door using your hidden blade and enter the next room. In this room, you will find a stone wall on the left as you enter. On the wall opposite the stone wall, you will find a small gap. Slide through it and get explosive. Now go back to the stone wall and destroy it using the explosive. Enter through the hole in the wall to collect the key sitting on a table.
Key 3: Evresin
The third and final key is in Gisacum Ruins in Evresin. Go to the location marked with a yellow arrow in the picture below. At the marked location, you will find some wooden planks covering a hole in the ground, Break the planks and jump down the hole.
Down the hole, you will find a door with the Hidden One’s symbol on it. Open the locked door using your hidden blade and enter the next room. In this room, you will find the key sitting on a table in the corner.
Lutetia Bureau Wealth Chest: Joyeuse Short Sword
After you have the three keys, go back to Lutetia Bureau and use the keys to open the door and enter the Bureau. After entering the Bureau, jump to the opposite corner and take an explosive. Then jump down and use the explosive to break the stone wall. Go to the next room through the opening in the wall. In this room, you will find a wealth chest containing Joyeuse Short Sword.
