The year is 1947. Moira Edwards Walker and her husband Thomas have settled into a normal life after adopting two orphaned Japanese girls who had been living in her cousin Margaret's home. But life does not remain ordinary. Abruptly, and without much explanation, Moira and Thomas leave their daughters in the care of Margaret and return to London where Moira, at Thomas' behest, becomes a "Watcher." She moves about Cambridge University and Highgate Cemetery where she photographs individuals who congregate near Karl Marx's statue. Amazingly, Moira does this without drawing attention to herself....