Andrew Marr looks at the life and reign of HM Queen Elizabeth II in this three-part series, which includes special interviews with Princes William and Harry, Princesses Beatrice and Eugenie, Zara Tindall and Peter Phillips, the Earl of Wessex, the Duke of York, the Princess Royal, David Cameron, Tony Blair, Sir John Major and President Obama.

In this first episode, with remarkable archive footage, Marr tells the childhood story of the young girl who never expected to reign. He looks closely at the influence of her grandfather, father and mother and the impact of the abdication, and hears from the Queen's grandchildren about what it must have been like to become queen at the age of 25.

Marr examines exactly what the Queen's role as head of state actually entails, and follows her to the Middle East and the USA to assess the global impact of the royal family on British trade and international relations.

Part 2

Part 3