Hitler's state-of-the-art killing machine the Bismarck was thought to be invincible but, for all the wild claims, it now lies at the bottom of the Atlantic Ocean.
Despite being the biggest, most powerful and most heavily armed battleship of her time, she was sunk just days into her maiden voyage.
Who Sank The Bismarck? features historical reconstructions and footage from the first manned dive to the Bismarck's wreck to reveal the German weaknesses - and Allied strengths - which led to the once-mighty ship's demise.