October 1914: the destroyer Svea emerged from the Stockholm archipelago bearing south-south-east. On board was Lars Tobiasson-Svartman, a naval engineer charged with making depth soundings for the Swedish navy. He is obsessed with measurement & precision, instincts reflected in his comfortable but cold relationship with his wife. Close to where soundings are taken, Lars rows out to a barren reef, presumed uninhabited, & discovers a young woman there. Despite her almost feral appearance, Sara stirs something in him. The mission is a success & the Svea returns to Gothenburg. Lars, however, remains haunted by this chance encounter, & feels compelled to return...