This quest begins immediately after Rathdown Build Up. To begin, you’ll need to speak with Barid at the Royal Hall in the southeast of Dublin.
Where to find Ciara, Flann’s Poetess
When you speak with Barid he’ll ask you to find Flann’s poetess, Ciara. She is most likely somewhere at the Dublin market, in the centre of the settlement. As you wander around the area you’ll begin to hear Ciara singing. Follow the voice until you find her at a table outside a tavern. When you approach her a cutscene will play, after which you’ll need to defeat two warriors in a fist fight. This should be a relatively easy fight, but it’ll be made all the easier if you have the Brush with Death (Way of the Raven) skill, which causes time to be slowed whenever you dodge an attack. Make use of dodge to avoid spam attacks from the warriors, and be sure to kite them if you need to. A good pattern to use is multiple light attacks followed by backing off or dodging to avoid retaliatory blows.
Once the warriors have been defeated, pick up Ciara from the floor and take her to a small pond nearby. All you need to do is drop her in the water to begin another cutscene. After the scene you can follow Ciara to the stables, where Barid is waiting. Get on a horse and ride to the ceremony with Barid and Ciara.
Where to Find the Missing Priest
When you reach the ceremony grounds located at Tara, another cutscene will play during which a guard notes the disappearance of a priest, with violence in their wake. Eivor and Barid offer to investigate. To begin, you’ll need to inspect the priest’s tent, then follow the patches of blood to the west. Be sure to examine the blood as you approach the hill to the west, then turn north and examine the patch near the tents there.
After you’ve examined the patch of blood near the tents in the north, Eivor will comment on the tracks of a cart. At this point a quest marker will indicate where you need to go, following the cart tracks to the northwest. When you reach the cart you’ll find the priest, dead and stripped of his clothes. From here, continue northwest to the bandit camp and kill everyone there. Be sure to loot the bandits for a letter indicating a plot to kill Flann. With the letter in hand, return to Tara and speak with Ciara to begin the ceremony, after which the quest will complete.