The film is based on Numa Sadoul's revealing interviews with Hergé from the 1970s, and goes into detail about Hergé's life and how the success of Tintin affected it. The film is based strongly around Hergé's experiences and state of mental health leading up to the writing of "Tintin in Tibet", often heralded as Hergé's most personal album. The history of Tintin is examined through Hergé's life and the way that he was affected by the growing popularity of his character.