The Twins — Alvin H. Franzmeier

When thirteen-year-old Orville Switzer discovers twin sisters lying frozen beneath the snow of a south St. Paul, Minnesota train yard in sub-zero temperatures in February 1938, Al and Tillie Freitag are suddenly pulled into a web of mystery, intrigue, mob violence, the German American Bund and pro-Nazi spies. Who murdered the twins and why?