The Mapping of Love and Death by Jacqueline Winspear

Maisie Dobbs is hired by the parents of American Michael Clifton to find the British nurse that he fell in love with while working as a cartographer for the British army during World War I. As it's 1932, Michael's remains have recently been recovered in France and it's obvious to Maisie and Michael's father from the postmortem that he was murdered, so that becomes part of Maisie's task as well. When the Cliftons are violently attacked and Maisie is mugged and her document case stolen, it becomes clear that someone is trying to impede the investigation. The mystery, along with the progression of Maisie's personal life, makes the book an enjoyable solid read.