The documentary "9/11," by French filmmakers Jules and Gedeon Naudet, had no initial objective of recording the September 11, 2001 terrorist attack on the Twin Towers in the United States. The film was meant to follow the story of firefighter James Hanlon, a rookie at the Duane Street firehouse in New York, with the aim of showing the routine of firefighting work and the challenges of the profession.
At the beginning of filming, Hanlon went to check a gas leak on one of the streets of the city, a routine job that would not bring major concerns. In the middle of filming this common call, the filmmakers began to hear a loud noise of a plane passing by.
The filmmakers ended up making one of the few video recordings of the moment the first plane hit the North Tower of the World Trade Center. The documentary then completely transformed and began to record the work of firefighters in the rescues after the attacks.




