Conclusion. Elizabeth I (Anne-Marie Duff) survives the threat of her cousin Mary, Queen of Scots, and four decades of palace intrigue. But her "finest hour," the defeat of the Spanish Armada in 1588, is marred by the death of "Robbie" Dudley (Tom Hardy), her "most faithful, most obedient servant." His replacement: another dashing young "Robbie" (Hans Matheson), the Earl of Essex and Dudley's stepson. William Cecil: Ian Hart. Lattice Knowles: Sienna Guillory.