The fourth and final season covers Henry's ill-fated marriage to Catherine Howard and his final, more congenial, marriage to Catherine Parr. The ageing King seeks military glory by capturing Boulogne, France. In his final hours, he is troubled by the ghosts of his dead wives.

Focuses on Henry's marriages to Jane Seymour and Anne of Cleves, the birth of his son Prince Edward, his ruthless suppression of the Pilgrimage of Grace, the downfall of Thomas Cromwell, and the beginnings of Henry's relationship with the free-spirited Catherine Howard.

Henry will do whatever it requires to marry Anne Boleyn, even by defying Pope Paul III. He prepares to take Anne on a royal visit to France, having demanded loyalty from the English clergy. The papacy in Rome organises an assassination plot against Anne but the assassins' attempts fail.