It is February 1945, and war-weary Londoners, having survived the Blitz, flying bombs and hardships of every kind, are now under assault from a new and even more deadly weapon: Hitler's V2 rockets. Returning on sick leave to his old hospital, St Martha's, after four years of active service, Captain Charles Bradley finds himself working alongside old colleagues once more when a nearby street market is hit and casualties are heavy. For the staff and patients of Alex Ward, weary but still cheerful after five long years of war, this is just the latest emergency in a series of tragedies that has left none of them untouched.