You get this quest after completing the Secret Service quest from your respective city. This quest isn't especially difficult but if you are below level 64 I recommend taking a group to help you out with this one.

Your first order of buisness will be to check out two tree houses in the Tenebrous Tangle realm. The first one is close to the waterfall you jumped off of in order to reach the Hidden Refuge. This tree house will be surrounded by droag unless someone has cleared them out. You will have to clear a path up to the very top of the tree house where you will walk around till you get the automatic update saying you have investigated that tree house. The second tree house is up the river and you will have to follow the same strategy as the first tree house to get to the top of it. After getting to the top of the second tree house you will get another automatic update for this portion of your Burglars Afoot quest.

After the second update you will now have to kill the Herald of Dar who walks a path from the Temple of Scale entrance to a Pyramid structure near the second tree house. Sadly the Herald of Dar drops only one note in a chest so you will have to kill him multiple times if you are in a group to get everyone the update.

 After reading the note you will now be instructed to kill the Soundless Guardian who spawns atop the Pyramid near the second tree house. It has been said that the Herald of Dar has to reach the pyramid to summon the Soundless Guardian.  The best strategy is to wait for the Herald to summon the Soundless Guardian then kill him then the soundless guardian. You will have to clear the bottom, middle, and top stonehewn drakes in order to make the Soundless Guardian attackable. Killing the Soundless Guardian will update your quest telling you to visit three locations. At these three locations you will see a body which you will have to "search" for clues. The Exact Locations of the Bodies are:  

• Gazer island: +1000 +467 -125
• Fear Tainted Island: +48 +244 +770
• Vultak Scavenging Island: -710 +171 -79

After obtaining the three clues you will recieve an puzzle card set in your inventory. You will need to answer the question correctly to break the code updating your quest. The answers are:

• 1. Crows Tavern
• 2. Irontoe's East
• 3. P.T. Irontoe
• 4. Kaladim
• 5. Crow
• 6. Crow's Resting Place
• 7. Fippy Darkpaw
• 8. Ping Fuzzlecutter

Upon breaking the code a timer will start where you must get the brooding isle finding evidence on a plank of wood. This plank is on the very right side of the island in the middle. If you go straight from the cloud transport up the side of the hill you will see it upon reaching the top part of the hill. Unfortunately a Savage Wyrm will be guarding the plank and you will need to quickly dispatch him to get to it in time. When you get to the note that is on the end of the plank of wood run back to the hill quickly because Drippy Darkpaw a 61 ^^ named gnoll will spawn.

Drippy Darkpaw is a pain in because he does a massive Knock up where he Knocks you up into the air and you take falling damage coming down (Update You no longer take falling damage). If you manage to keep him stunned or knockdown for a bit he shouldn't be too much of a problem. After killing him you will be given two items and one of those items is a key. On the brooding island head to +564 -146 +641 to find a chest and upon opening a chest you will recieve two more items. The first notable item is the Disk of Blyze which will give you the next step in the Qeynos Claymore Quest line.

The other item you recieve will be Drippy Darkpaw's note. You will need to examine the Disk of Blyze which will give you a new quest Coin Operation: The Sanctum of The Scaleborn. That quest takes place solely within the Sanctum of the Scaleborn and gives a great reward upon completion.