In the opening episode, following the death of Queen Elizabeth I in 1603, King James VI of Scotland claimed the throne along with a new title of King James I of England. He faced numerous attempts on his life, including the notorious Gunpowder Plot, and the threat of the terrifying Thirty Years War which was raging on the continent. For the aristocratic Wynn family of North Wales though, this new reign of the Stuarts provided great opportunities, but also some terrible dangers.

In this episode of the historical documentary, Professor Kate Williams explores the reign of King Charles I who succeeded his father King James I in 1625. The ties between the Wynn family and the ruling Stuarts grow ever closer as Sir Richard Wynn joins his King on an ill-fated voyage intended to gain the Infanta of Spain's hand in marriage. Having failed, Charles marries the daughter of the King Of France instead, putting a Catholic Queen back on the throne. Religious upheaval along with Charles' dismissal of Parliament and authoritarian rule eventually leads to a civil war. In the end, a king is beheaded, and a commoner named Oliver Cromwell seizes power.

In this episode, Professor Kate Williams looks at how Oliver Cromwell's Commonwealth came to an end soon after his death when in 1660 an exiled King returned to London with enormous fanfare. King Charles II's reign was a dramatic shift away from the rule of the Puritans that preceded him but the dual tragedies of the worst outbreak of plague in generations and the Great Fire Of London struck the nation's heart. The Wynn family of North Wales, having suffered under Cromwell, returned to royal favour.

In the final episode, Professor Kate Williams looks at King James II succeeding his brother King Charles II in 1685. He was a Catholic monarch of a Protestant nation and attempts had already been made to prevent him from claiming the throne. The last of the Stuart Kings, he reigned for only three years and it was his own daughter, Mary, who caused his downfall. She, along with her husband William of Orange, overthrew the House Of Stuart and sent King James II into exile. It was also the end of the powerful Wynn family, their status rose and fell with the Stuart Kings they served.