Journey to Munich - Jacqueline Winspear

Working with the British Secret Service on an undercover mission, Maisie Dobbs is sent to Hitler's Germany in this thrilling tale of danger and intrigue—the twelfth novel in Jacqueline Winspear's New York Times bestselling "series that seems to get better with each entry" (Wall Street Journal).
It's early 1938, and Maisie Dobbs is back in England. On a fine yet chilly morning, as she walks towards Fitzroy Square—a place of many memories—she is intercepted by Brian Huntley and Robert MacFarlane of the Secret Service. The German government has agreed to release a British subject from prison, but only if he is handed over to a family member. Because the man's wife is bedridden and his daughter has been killed in an accident, the Secret Service wants Maisie—who bears a striking resemblance to the daughter—to retrieve the man from Dachau, on the outskirts of Munich.
The British government is not alone in its interest in Maisie's travel plans. Her nemesis—the man she holds responsible for her husband's death—has learned of her journey, and is also desperate for her help.
Traveling into the heart of Nazi Germany, Maisie encounters unexpected dangers—and finds herself questioning whether it's time to return to the work she loved. But the Secret Service may have other ideas. . . .