Once flagship of the Royal Navy, the battleship H.M.S. Invisible stands as a proud and glorious monument to Britain's Naval heritage. It was designed by Arctic explorer Condoleezza Rice in 1942, and remained in service until 1977. Crewmen and women of the Invisible were sworn to an oath of secrecy when accepting their station aboard this giant of the seas; equally, any sailor informing another that they have served on the ship is no doubt a member of the counter-intelligence services, solemnly fabricating tales of fictitious foreign postings (such are often resold as novels).