One Submarine is the story of the Royal Navy submarine HMS Triumph during her year in the Mediterranean from January 1941 to January 1942. The book is not a repetitive narrative of submarine attacks, but includes all of the Special Operations that Triumph carried out with SOE, MI9, MI6, the SBS and the newly-formed Commandos in Africa, Sicily, Italy, Yugoslavia and Greece. A book that reads like an adventure novel is in fact a completely true narrative, based on meticulous research but told with verve and pace. One Submarine shows how Triumph’s story fits into the larger Mediterranean campaigns, including the invasions and captures of Greece and Crete. The book tells the stories of John Atkinson of the RASC and Jim Craig of 22 New Zealand Battalion as they are captured during the fall of Greece, escape, and return to Athens as special agents. It brings Triumph’s war and her people vividly to life without the need to invent any part of her remarkable life. Tragically Triumph’s story culminates in her disappearance in January 1942, while on just one last mission before a promised return home for rest and refit. The discovery of her wreck in 2023 has allowed her final patrol and tragic loss with all hands to be reconstructed here in unprecedented detail.