After Tataru updates you with the latest details in the search for the missing Scions, you depart for a private audience with Aymeric.
This quest is available if you have completed the quest Heavensward.
Starting the Quest
Talk to Alphinaud in Fortemps Manor in Ishgard to begin the quest. There will be a cutscene.
Speak with Aymeric
Use an Aethernet Shard to go to the Forgotten Knight Aethernet Shard, and go east through the double doors behind Firmalbert. Talk to the Temple Knight Guard and say Yes to proceed. 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.
Speak with Lucia
Talk to Lucia to proceed.
Speak with Tataru
Go outside and turn left, and go into the Forgotten Knight. Go downstairs and talk to Tataru.
Speak with Lucia Again
Go upstairs and outside, and turn right and go through the doors. Talk to Lucia to complete the quest.
Next Main Scenario Quest
After you complete the quest, talk to Alphinaud to accept the next quest: Breaking the Cycle.