Queen Elizabeth I, conqueror of the Spanish Armada, Tudor defender of the Protestant faith, the headstrong Virgin Queen who refused to marry, but out of all of her challenges her most grueling battle happened to be with another women, her own cousin, Mary Stuart Queen of Scots.

Elizabeth had not faced a more relentless threat to her crown or her life, both claimed the English throne, two Queens on opposite sides of the greatest conflict of their time, Protestant and Catholic, Tudor and Stuart, and that most ancient of rivalries, English and Scottish.

This BBC special is a chronicle of love turned to hatred, of trust betrayed by plot and bloodshed, dramatised purely from the original words of the two queens and their courtiers.