Escape - Affair at Mandrake

British Colonel Guy Baker stood on the beach at Dunkirk, watching what was left of his battle-weary troops wait their turn to board the little boats back to England. While inspecting the captured prisoners, Colonel Baker notices one that looks identical to someone he knew before. He asks him a question, but the prisoner replies that he does not understand English. The Colonel says "Sergeant Major Holloway, shoot that man!" Holloway replies "no sir, I cannot. It's against the King's regulations to kill a prisoner of war". Colonel says "that man is a traitor, I will prove it to you. Get his service book". His name according to his German service book is Wilfred Dorf, a name not familiar to Colonel Baker. He says "I could have sworn he was a childhood friend from London named Ferdy Shotz. It seems that I must have made a mistake".