The true story of the loss of submarine HMS Thetis is still shrouded in mystery, even now, some seventy-five years after her tragic sinking. On 1 June 1939, HMS Thetis sank in Liverpool Bay on her maiden dive with the loss of ninety-nine lives. It was the worst peacetime submarine tragedy ever to be suffered by the Royal Navy. As soon as the impending disaster was reported, a massive rescue operation was mounted by the Royal Navy, but following a catalogue of misunderstandings, political posturing, red tape and sheer incompetence, the operation ended in abysmal failure with only four of the crew being rescued. There were many ongoing recriminations and a number of legal battles following the Royal Navy’s private inquiry and the subsequent public inquiry. Even after such a forensic examination, no one was held to be culpable for the disaster. As a result of media coverage at the time, a number of conspiracy theories were spawned, some gaining more credence than others in light of the inconclusive findings of the official reports. In Thetis: Submarine Disaster, David Paul, having studied the events surrounding the tragedy of HMS Thetis for many years, examines the issues which led to the disaster and draws some convincing and devastating conclusions.