Speak to Sir Tiffy Cashien to start the quest. He will tell you that a Pest may have escaped the Void Knights' Outpost. He wants you to interview the residents on the island to find out how it could have escaped. Go to the Void Knights' Outpost and speak to Commodore Matthias. He can be found in the north-eastern part of the island in the north building. Though skeptical of the claim a pest escaped, he will tell you to speak to Captain Tyr to help in your investigation. Captain Tyr is to the south out in the open. To remember which people you have already spoken with, view your quest journal.