The first episode, "Shadows of Doubt", starts with Miller in the Reading Room at the British Museum describing the purpose of the series, and gives a brief montage of the interviewees. Miller starts his journey in New York City and states that the attacks of 11 September 2001 were "inconceivable without religion". Miller goes on to describe how he is conducting the series to explore the history of atheism, but he says he is rather "reluctant" to call himself an atheist because "it hardly seems worthwhile having a name for something which scarcely enters my thoughts at all". There follows a brief montage of people explaining their atheism: Sir Geoffrey Lloyd, Polly Toynbee, Gore Vidal, Steven Weinberg and Colin McGinn. Miller then describes his Jewish upbringing sitting in the pews of the New London Synagogue in St John's Wood.