The film is based on the memoirs of Hawking's wife Jane Wilde. It took three years for the producer and screenwriter to persuade her to agree to adapt the memoir into a movie.
Hawking himself admired the film very much, and he agreed to use his real "voice" () in the film.
In addition to the real "voice", the props used in the film, including the Queen's Medal of Honor and signed papers, were also provided by Hawking himself.
Screenwriter Anthony McCarten spent ten years from writing the screenplay to the film's release. He became interested in Hawking's life after reading "A Brief History of Time" in 1988. After reading Jane's memoirs in 2004, he began to write scripts.
Since the film was not filmed in chronological order, this created a big problem for Redmayne as Hawking, because in different scenes, Hawking's muscles degenerate to different degrees, and he must accurately interpret Hawking's state at that time.
"Theory of Everything" held its world premiere at the Toronto Film Festival in the fall of 2014, when Hawking himself was a member of the audience. After the movie was over, his secretary wiped a line of tears from his cheeks.
