Russia 1918. A mother dies in childbirth whispering a final message to her husband. He escapes from the turmoil of the Revolution, leaving his position as submarine Commander behind and takes the baby girl to live on Shetland. The emergence of the Second World War finds him returning to his homeland on a secret and dangerous mission helped by the Norwegian resistance and partisans. Here he begins to piece together the mystery surrounding his wife's last words and discovers the shocking betrayal by a priest all those years ago. A desperate search now begins.