In the Second World War, the Rock of Gibraltar stood like a sentinel at the gateway to the Mediterranean. Whoever held it could open or close the sea lanes to North Africa and beyond. To Britain it was a vital stronghold, but by 1940 it looked vulnerable. Spain was under Franco's rule, sympathetic to Berlin, and German planners drew up schemes to seize the fortress in one swift move. It was in this climate that a plan was conceived that bordered on the unimaginable. A small group of men would vanish from the surface of the Rock and take up residence in a chamber hollowed out within its limestone core. They would not leave again until the war ended. Dur: 29mins File: .mp3