The fifth hour explores the post-World War II era, when rising evangelist, Billy Graham, tried to inspire a religious revival that fused faith with patriotism in a Cold War battle with "Godless Communism." As Americans flocked in record numbers to houses of worship, non-believers and religious minorities appealed to the U.S. Supreme Court to test the constitutionality of religious expression in public schools. And civil rights leader Martin Luther King Jr. emerged as a modern-day prophet calling upon the nation to honor both biblical teachings and the founders' democratic ideals of equal justice. The final hour of "God in America" brings the series into the present day, exploring the religious and political aspirations of conservative evangelicals' moral crusade over divisive social issues like abortion and gay marriage. Their embrace of presidential politics would end in disappointment and questions about the mixing of religion and politics. Across America, the religious marketplace expanded as new waves of immigrants from Asia, the Middle East and Latin America made the United States the most religiously diverse nation on earth. In the 2008 presidential election, the re-emergence of a religious voice in the Democratic Party brought the country to a new plateau in its struggle to reconcile faith with politics. "God in America" closes with reflections on the role of faith in the public life of the country, from the ongoing quest for religious liberty to the enduring idea of America as the "city on a hill" envisioned by the Puritans nearly 400 years ago.