In 1997, Mangold had already germinated the idea of filming "Walk with the Song", and informed his wife and producer Kathy Conrad, the two negotiated to find Cash’s friend James Ketcher. People soon started working on this movie about Cash. In the following years, the film’s main creators frequently contacted Cash and Joan and listened to them telling them about their early rock and roll, life experiences and long love journeys. During this period, the director Mangold never shy away from sharp issues, and Cash fully Trust him and answer calmly. Mangold was moved by the love of the two, and he realized that love was part of their musical journey.
While working on the script of the film, Mangold and the screenwriter Gil Dennis also checked the two autobiography that Cash had published, namely "ManInBlack" in 1986 and "Cashhe Autobiography" in 1997, and they studied Cashhe Autobiography in 1997. He Joan's songs, search for the records that Cash recorded in his early years. These records are not only rare due to the age, but also a window into the thoughts and emotions of Cash at the time. Joan and Cash died in 2003. Before that, they had read multiple versions of the script and provided timely feedback.
