Click the door of the Peacock Club ( -225, 146, 82 ) /waypoint -225, 146, 82 to receive this quest and then enter it by clicking on the knocker.
Speak to Peacock Lord Wad'dah Haz'Iz, he will test you by telling you to take Ceremonial Cutthroat Banners from each Court. You get these by entering special instanced versions of the Court of Truth, Coin and Blades by entering them through the back entrance. You will need the Back Entrance keys that drop from the palace sweepers to do this.
Kill a palace sweeper in Maj'Dul for keys to enter each Court. The colour of the palace sweeper's robes correspond to the key droped: red = Truth, yellow = Coin and blue = Blades.
These spawn at ( -228, 160, -128 ) /waypoint -228, 160, -128. The spawn time is approximately 5 minutes. After spawning the palace sweeper will wander around at the nearby market, star gazer plateau above the market, outside the Sultan's Palace, past the Court of Truth and finally down into the poor area near the Peacock club where she despawns around ( -114, 156, 47 ) /waypoint -114, 156, 47. I had to zone out and back in before these began spawning.
Only one palace sweeper will spawn at a time and it is possible to get the same NPC spawning several times. For example, I killed the Blades (blue) sweeper and by the time I returned the same Blades sweeper was up again.