Hiltgunt Zassenhaus (1916–2004) was an interpreter during World War II, well-known for helping prisoners held by Nazi Germany. While she interpreted for Scandinavian prisoners under the guise of censoring their correspondence, Zassenhaus instead added information and documented their locations in journals she later turned over to human rights authorities. She attended the University of Hamburg and the University of Copenhagen, and after the war, completed a medical degree at the University of Bergen. She documented her story in Walls: Resisting the Third Reich—One Woman’s Story.

Katherine Paterson is the author of over 35 books including the Newberry Medal-winning titles Bridge to Terabithia and Jacob Have I Loved and the National Book Award–winning titles The Master Puppeteer and The Great Gilly Hopkins.