There were many heroes in the City Police in the Second World War, but we choose Staff Sergeant Mitchell of the Special Constabulary. He nearly lost his life in the course of duty when an incendiary bomb exploded while he was walking on Fleet Street on 23rd May 1941. His book of regulations in his top pocket saved his life! You can see the damage the shrapnel made in the book. Here's the piece of shrapnel that was embedded in the book with a ruler for scale.