Fifteen years later, Petrus has succeeded his uncle, naming himself Valerius II and making Alixana, formerly Aliana, his empress. Valerius II commissions a great sanctuary to Jad and summons Martinian of Batiara, a renowned mosaicist, to decorate it. The royal request is sent with Pronobius Tilliticus, an Imperial Courier, who delays delivery of the message while pursuing personal pleasure along the road. Martinian, partially on whim and partially believing himself too old to travel, causes Tilliticus to mistake his friend and colleague Caius Crispus ("Crispin") of Rhodias for him, delivering the message in a public fashion. Crispin is reluctant to accept the prestigious summons, having lost the desire to live when his wife and two daughters died of the plague the previous year. The summons having been much delayed, the season no longer allows Crispin to sail to Sarantium; he must take the road. Martinian sends Crispin to talk to his old and well-traveled friend Zoticus for advice on his journey. Zoticus reveals himself to have some supernatural powers and gives Crispin a mechanical bird, Linon, that is alive, being able to both talk to him aloud and within his mind. He also gives Crispin the name of his daughter and another person in Sarantium who may be able to help him.