Portelaine directs you to the knight stationed at Dzemael Darkhold to learn more about Biggs and Wedge's whereabouts.
This quest is available if you have completed the quest Casing the Castrum.
Starting the Quest
Talk to Portelaine in the Observatorium in Coerthas Central Highlands to begin the quest. There will be a cutscene. This one is important, so it is recommended to watch it either now or via the Unending Journey in an inn room.
Show the Letter of Introduction to Bricelt
Go west to where the orange arrow is pointing in the minimap. Talk to Bricelt and hand over the letter.
Speak with Pierremons
Go southwest to where the orange arrow is pointing in the minimap. Talk to Pierremons to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Pierremons to accept the next quest: Footprints in the Snow.