Upon finishing both The Kayran and Indecent Proposal quests, you’ll find Triss waiting for you outside of Loredo’s estate. She tells you that one of Iorveth’s top men, Ciaran, is being held captive on one of Loredo’s prison barges at the docks. It’s up to you to find him and extract any information possible about the mysterious assassin.
Follow Triss to the barge, which sits at the end of the pier by the entrance to Flotsam. Triss tells you that the prisoner has been wounded, and she plays the part of a healer in order to bypass the guards. You won’t have it quite so easy. If you accepted Loredo’s offer in Indecent Proposal, you can simply walk past the guards. Oherwise, you’ll have to rely on persuasion or Axii.
Head to the lower deck, where you’ll find Ciaran. He is wounded and can barely speak. Triss and Geralt combine their magic to heal him just enough to speak. In order to cast the spell you’ll have to complete a quick time event by repeatedly clicking the left mouse until the onscreen meter fills up. In return for the healing, Ciaran tells you that the kingslayer betrayed the Scoia’tael with whom he was allied. You’ll also learn the name of your adversary: Letho.
As Geralt is interrogating the prisoner he will have a flashback revealing another tidbit of his past. Ciaran takes notice of this and tells Geralt about the Roses of Remembrance which grow amongst the elven ruins. Triss confirms that she had spoken with the elf Cedric earlier, and they both agree that if Geralt can get his hands on the petals of these roses, he may be able to restore his memory. She agrees to go find some. It is up to you whether or not you wish to accompany her. Doing so will initiate a main quest called The Rose Of Remembrance.
Although going to the elven ruins with Triss is entirely optional, it is recommended that you do it. Following Triss will lead to some interesting conversations, as well as a few useful items and extra experience points. Agree to accompany Triss and leave the barge for now. There isn’t much more you can do here until you’ve explored the elven ruins for yourself.