Watch Soap2day. Hosted by Edward Mulhare, Secrets of the Unknown: The Titanic unravels the mysteries surrounding the 1912 sea disaster which sent 1,500 people to a watery grave in the mid-Atlantic after colliding with an iceberg. Did the luxury liner's crew have fair warning, but fail to react appropriately? The program presents new evidence and insights into the calamity which still baffles historians.