Discover the story behind the scenes of the band's fifth studio album Hotel California, one of the best-selling albums of all time. Henley said about this work: 'They are the same themes that run through all of our work: loss of innocence, the cost of naiveté, the perils of fame, of excess; exploration of the dark underbelly of the American dream, idealism realized and idealism thwarted, illusion versus reality, the difficulties of balancing loving relationships and work, trying to square the conflicting relationship between business and art; the corruption in politics, the fading away of the Sixties dream of peace, love and understanding.

Fights within Eagles were common long before Hotel California. They started as four equal partners. Gradually the power shifted toward Henley and Frey, which Meisner and Leadon resented. Leadon left first because the band progressed from country to rock. He also wanted to live a healthy life in a band that lived extremely unhealthy. Even though they made many wonderful songs, things were far from smooth in the studio.

Last part of the documentary begins with the period following the breakup, with brief accounts of the careers of individual members of the band and by the reunion of the band in 1994, followed by the 1990s and 21st century phases of the Eagles. It documents their successful tours, the dispute with Don Felder and the period after his dismissal. It concludes with the band members looking back assessing their actions and career, with contributions from other people who knew them.

In the fourth part of the series, Diarmaid MacCulloch makes sense of the Reformation, and of how a faith based on obedience and authority gave birth to one based on individual conscience. He shows how Martin Luther wrote hymns to teach people the message of the Bible, and how a tasty sausage became the rallying cry for Swiss Reformer Ulrich Zwingli to tear down statues of saints, allow married clergy and deny that communion bread and wine were the body and blood of Christ.

How did Jeffry Epstein acquire the fortune that protected him for so long? As police and FBI gather mountains of evidence against him, Epstein goes on the offensive. The US attorney Alexander Acosta met with Epstein's lawyers. Not only was the indictment gone, the FBI case was stopped.

Al-Khalili travels to northern Syria to discover how, a thousand years ago, the great astronomer and mathematician Al-Biruni estimated the size of the earth to within a few hundred miles of the correct figure. He discovers how medieval Islamic scholars helped turn the magical and occult practice of alchemy into modern chemistry. In Cairo, he tells the story of the extraordinary physicist Ibn al-Haytham, who helped establish the modern science of optics and proved one of the most fundamental principles in physics - that light travels in straight lines. Prof Al-Khalili argues that these scholars are among the first people to insist that all scientific theories are backed up by careful experimental observation, bringing a rigour to science that didn't really exist before.