The Hinterkaifeck Murders remain one of Germany’s most chilling unsolved crimes. In 1922, six people living on a remote farmstead near Munich were brutally murdered — including Andreas and Cäzilia Gruber, their daughter Viktoria, her two young children, and a newly arrived maid. Each victim was lured one by one into the barn and killed with a mattock, a farming tool. What horrified investigators was the precision and silence of the attacks — no one heard screams, and the killer showed no urgency