Secret Service Quest/Spoiler

Mission 1 - Deliver a letter
First you have to talk to the NPC uncle in Venore, he is south of the boat, 2 floors up. Say hi, join, yes. Then ask him for your first mission. He tells you to deliver a letter to Gamel in Thais. Coming from the ship, you will find Gamel in the first house west of the ship, one floor down. Say hi. He will summon 2 Bandits now. Kill them and say hi again. Give him the letter. Return to Uncle and say mission, yes.

Mission 2 - Deliver beer
Ask Uncle for a mission again. He will tell you to bring a barrel of beer (It weighs 85 oz, so have some cap ready!) to Carlin, the Secret Taverna in the sewer s. Once you down into the sewers, there will be two summoned Amazons. Talk to the NPC behind the counter. After he got the barrel of beer return to Uncle and say mission, yes once again.

Mission 3 - Steal a document
This time Uncle wants you to steal a document of a certain type from the castle in Thais. Travel there. In King Tibianus' room, you can find a ladder in the bottom left corner of the room. Go up there. You will see a special door on that floor, go there, open it and get the document by using something in this room. Return to Uncle.

Mission 4- Killing a black knight
Now you will have to kill a black knight in the Venore Swamp.