One Sunday morning in April 1943, during the dark days of WW2, four teenage boys made a terrifying discovery that would baffle the police and remain a mystery for over 70 years. The boys were searching for birds nests at Hagley Woods, a private estate near Birmingham in England’s Midlands. Climbing up an ancient old wych elm tree, 15-year-old Bob Farmer saw something truly terrible. Looking down the hollowed out trunk, Farmer noticed a strange object staring back at him from the dark interior. The teenager was horrified when he realized it was a human skull.