In 1944 during WW2 codenames for the D-Day operation started appearing in the Daily Telegraph newspaper. Was this a German spy at work? M15 were determined to find out. Twitter: the historical crimes and criminals podcast Ko-fi.com/historicalcrimespodcast www.telegraph.co.uk/news/2019/06/05/d-day-clues-hitler-had-done-telegraph-crossword/ www.warhistoryonline.com/world-war-ii/crossword-puzzle-nearly-ended-dday.html www.theguardian.com/crosswords/crossword-blog/2014/may/12/crossword-unsolved-mystery-d-day-puzzles-leonard-dawe www.history.co.uk/articles/the-unsolved-mystery-of-the-d-day-puzzles wargaming.com/en/news/jasper_maskelyne