The American Agent by Jacqueline Winspear

Private detective Maisie Dobbs is asked to investigate the murder of American journalist Catherine Saxon in London. Catherine was reporting on life as the Nazis bombarded the capital during the Blitz. In addition, Catherine came from a very wealthy family in the States and both her father and brothers disapproved of her choice of career. She also had suffered personal loss while in Spain before the war. Could any of that be connected to her death? It's up to Maisie and her assistant, Billy, to find out the truth in this case that seems to have lots of suspects. In addition, Maisie is on edge because her adoption of Anna has been postponed and she, like most in England, are finding their everyday lives continually upended because of the war. The American Agent is another well-researched and engaging entry in the long-running Maisie Dobbs series.