A young Princess Elizabeth marries Prince Philip. As King George VI’s health worsens, Winston Churchill is elected prime minister for the second time.

When dense smog cripples London for days and creates a serious health hazard, Churchill’s inaction leaves him vulnerable to his political enemies.

Margaret and Peter come to Elizabeth with a request. With a royal scandal about to break in the newspapers, the Queen Mother intervenes.

As the Soviets test the H-bomb, both Churchill and Eden have major health crises. Angry about her inadequate education, Elizabeth hires a tutor.