This film tells the story of the reign of King George VI and Queen Elizabeth, from its difficult beginnings after the abdication crisis of 1936, focusing on the unique relationship of a king and queen whose great love for each other and strong sense of duty won the hearts of a nation. Bertie had grown up in the shadow of his confident, charismatic elder brother, the future Edward VIII. However his marriage to Lady Elizabeth Bowes-Lyon on 26 April 1923 was perhaps the turning point of his life.

Their happy family life with the two young princesses, Elizabeth and Margaret, born in 1926 and 1930, brought a welcome air of freshness to the British royal family. When war broke out in 1939, the King and Queen remained in London. They threw themselves into the tasks of maintaining the nation's morale, making wartime broadcasts to the nation and visiting the people whose homes had been destroyed by bombs. In the years following the war, the king's health began to deteriorate. Despite this, there were still happy times ahead. Bertie and Elizabeth celebrated their silver wedding in 1948 and later that year became grandparents with the birth of Prince Charles.

The king's death on 6th February 1952, despite his recent illness, came as a surprise. At his lying-in-state, people formed queues to pay tribute to a king who had put duty first.