The Thieves’ Code is a highly missable side quest in Kingdom Come Deliverance: 2, which only appears if you have made specific choices beforehand. In fact, the choices are so subtle, some players might not even notice. In this article, we will take you through all there is to know about this quest.
How To Start The Thieves’ Code In Kingdom Come: Deliverance 2

You need to talk with Chenyek in The Hole in the Wall tavern at southern Kuttensberg to get this quest. However, it is not as easy as it sounds – you need to complete a few perquisites in order to start the conversation leading up to the quest. First of all, you need to be polite and win the skill checks with Chenyek during “Into The Underworld” quest’s ‘Find Goatskin’ objective. If you do that, he asks you to talk to him once you are done with your current task.
Upon doing so, he will assign you the “Feast for the Poor” side quest, and only after completing that can you talk to him for the Thieves’ Code quest. If you threatened or misbehaved with Chenyek during “Into The Underworld”, he dismisses you and the opportunity for this quest is lost forever.
How To Complete The Thieves’ Code In Kingdom Come: Deliverance 2
You must track down the meaning of symbols drawn all over houses in Kuttenberg to complete this quest. Chenyek tells you that these were left before the Guild or Sigismund came to Kuttenberg, by a band of thieves to mark potential houses.
Talk to Knuckles

This is an optional objective, where you need to make a choice. Knuckles agrees with Chenyek’s interpretation of the symbols being useful, but wants you to tell him about your findings instead of Chenyek. Even if you make a choice during this conversation, it isn’t locked in and you change your decision until the end of the quest.
Talk to Hynek

Go to Hynek’s house in northern Kutternberg, where you will find him dead and Hog standing over his corpse. Upon questioning, he tells you they had a disagreement, which resulted in Hynek on the floor. Additionally, he reveals that Hynek has a parchment on him that might help to understand the meaning of symbols. Loot his body and read the parchment to find a riddle.

Go back to Chenyek, and ask him if he knows anything about the riddle. He tells you that the riddle might be pointing to a fountain, of which there is only one inside Kuttensberg.
Find The Thieves’ Hideout

Head over to the Fountain on Vintner’s Street POI at eastern Kuttensberg. According to the riddle, you must wait for the midday bell and observe the shadows. Skip the time exactly to 12:00, and you will see the shadow going towards a trader’s shop nearby. Go inside and into the back, where you will find a door leading to the basement.

Go downstairs, and unlock the door just beside the stairs. This is a hard difficulty lock, so you might want to drink a Quickfinger potion. Proceed ahead to find another locked chest, but this time it is an easy one. Open it and take the Thieves’ note parchment.
Turn over the Findings

Return to the The Hole in the Wall tavern, and make your choice. Remember, if you choose to show your findings to Hynek first, you can still show it to Chenyek, but not the other way round. Chenyek also tells you one of the houses with the symbol on it is nearby, meaning it belongs to someone rich and can be robbed if Henry prefers to do so.
You are rewarded with 100 groschen for completing this quest.