Gran and company are under fire and trapped by Imperial Army General Furias, who intends to recapture Lyria. However, Rackam, the helmsman, gives them a way out. They propose hiring him as a helmsman to get them off the island, but he refuses and tells them he doesn't want to fly unless it's with the Grandcypher, the old airship that has captivated him since he was young.

After saving the Port Breeze Archipelago from the threat of Tiamat, Gran and company set off for the Valtz Duchy. Siero introduces them to a Valtz Duchy "special operator," who asks them to search for the missing Archduke Tzaka, the most powerful person in Valtz. They take the job and begin investigating right away, but someone is following them...