The Mystery surrounding the disappearance of the Ninth Legion is one that, since Rosemary Sutcliffe's book The Eagle of the Ninth and the follow up radio plays, TV series and Hollywood movies, has captured the public imagination. Many academics, archaeologists and popular writers have speculated as to what happened to the elite fighting unit and whether they were destroyed in Britain, mutinied or were simply transferred (and ultimately wiped out) somewhere else in the Empire. This book presents the first detailed forensic examination of both archaeological and historical sources, analyzing the primary dataset rather than simply speculating on what has been said before. The conclusions reached in this study help to resolve the disappearance of this unlucky Roman military unit once and for all. This book will intrigue and enthrall the general public and academic community alike.