When the college's controversial pacifist founder and principal, Greville Liddicote, is murdered, Maisie is directed to stand back as Scotland Yard spearheads the investigation. She soon discovers, however, that the circumstances of Liddicote's death appear inextricably linked to the suspicious comings and goings of faculty and students under her surveillance.

To unravel this web, Maisie must overcome a reluctant Secret Service, discover shameful hidden truths about Britain's conduct during the Great War, and face off against the rising powers of the the Nazi Party in Britain—all as the storm clouds of World War II gather on the horizon.