Mary Queen of Scots was a romantic and tragic figure. The story of the ‘Casket Letters’ adds richly to the enigma and mystery – eight letters, a love sonnet and two contracts, allegedly written by Mary to her lover, implicated Mary in her husband"s murder and ‘proved’ her adultery. This forensic re-examination of the controversy, the latest historiography, and the huge literature it has generated together with an accessible presentation of the ‘Letters’, is a detailed and powerful study for both scholar and general reader and illuminates sharply the dramatic events leading to Mary’s imprisonment and eventual execution.