Surgeon Frederick Welin has lived alone on a deserted island, in self-imposed exile, since he was disgraced for trying to cover up a mistake on the operating table. Then, one morning, he sees a figure struggling across the ice and realises that his past is about to catch up with him.
The figure approaching him is Harriet, the only woman he ever loved, the woman he abandoned forty years ago in order to study in America. Now Harriet has tracked him down to ask him to honour a promise made many years ago: to take her to a beatiful lake, hidden deep in the forests of northern Sweden. But Welin soon discovers that Harriet has left his biggest surprise until last.