On the night of 4 July 1943, transport aircraft Liberator AL523 took off from Gibraltar's North Front tarmac and within moments crashed into the sea with only one survivor, the pilot. The commander-in-chief of the Polish army and prime minister of the Polish government-in-exile, General Wladyslaw Sikorski, was dead.Rumours as to the cause of the crash abounded. Was it pilot error? Was it, as officially classified, merely an accident, or was it, as the authors conclude in this riveting and meticulous study, an act of sabotage?In this extensive piece of research, Chris Wroblewski and Garth Barnard examine numerous primary sources, including the complete court of inquiry transcripts, produce detailed analysis of aircraft components and systems and unearth many little-known eyewitness accounts to give this investigation a compelling conclusion. Within the book the authors also dispel several conspiracy theories that have emerged since this catastrophe; particularly that this event was a disastrous assassination attempt with blame on the British, Soviets and Nazis.This is an exhaustive piece of investigative journalism that puts the record straight once and for all.