British author Gardner (1926–2007) offers an authentic view of London in peril from V-1 rockets in his fifth and presumably final Suzie Mountford WWII mystery (after 2006's Troubled Midnight
). During the summer of 1944, policewoman Suzie Mountford of the Reserve Squad and her boss (and lover) Tommy Livermore go into action after a V-1 lands on a convent, killing several nuns—one of whom turns out to have been murdered beforehand, another of whom proves to be a man. As Mountford and Livermore try to identify the victims, they realize that what first appeared to be an unusual murder case is actually part of a larger and potentially deadly conspiracy. Despite stock characters out of a 1940s film and period Britishisms that may puzzle the average U.S. reader, those with a taste for old-school tales of war-time intrigue should be satisfied. (Aug.)