It is the first part of a trilogy detailing an alternate history in which human efforts were able to prevent Doggerland from being flooded.

Representing the Pretani leader are brothers Gall and Shade, who share the house with Zesi and her 14-year-old sister Ana.

To make matters worse, Gall kills a member of the neighbouring "Snailhead" tribe during a communal hunt.

During the tsunami, Ana witnessed seabed formations resembling Etxelur's religious symbols, and, believing them to hold spiritual significance, ultimately resolves to build a dyke to hold back the sea and enable the formations to be reached once again.

She breaks one of the giant pools which holds water that is meant to flow back into the sea and kills a Snailhead child.