Tané wakes up on the seashore and sees a stranger appear on the scene. The man is later revealed to be a Westerner called Triam Sulyard. The stranger’s presence scares Tané, because Seiiki, the Eastern country in which she lives, forbids the entry of foreigners, believing they may carry the “red sickness” (an infectious disease). Tané is herself breaking rules by being on the water’s edge, as she is supposed to be cloistered before “Choosing Day” the following morning, when she will learn which occupation she will join. Tané’s desire is to become a “Miduchi”—a member of an elite force that rides the great water dragons. In the East, dragons are considered gods.

Disclosing the stranger’s presence to the city’s watchguards would mean Tané admitting to her own transgression, so she blindfolds Sulyard and takes him to her trusted friend Susa. Susa and Tané are both orphans. In Seiiki, most children train from childhood to join public offices, such as the army and the house of scholars.

Susa takes Sulyard to the island of Orisima, where he can hide at the home of surgeon Niclays Roos, a Westerner exiled on the island. Niclays reluctantly agrees to host Sulyard for a night in exchange for money for his research supplies.