In our third and final episode of Dig WW2, historian Dan Snow travels to Lough Foyle to dive on a Flying Fortress that never made it on a bombing raid. Unearthing stories of the crew, we hear how they miraculously survived the crash helped by a local woman and her sailboat. He then heads to the shores of Lough Neagh where, at RAF Cluntoe, pilots and crew were trained for flying missions all over Europe. Finally, he reveals the climactic end of the Battle of the Atlantic on the River Foyle docks, where the German navy surrendered their U-boat fleet and from where they set out to be sunk off Malin Head. Dan returns to this U-boat graveyard to dive on one very special submarine, which could have spelled victory over Germany, but arrived just too late.