The making of the film led to a legal battle between star Mel Gibson and Voltage Pictures, because the latter wouldn't allow Gibson and original director Farhad Safinia to film scenes on location in Oxford, England. Because the film was already over budget and behind schedule, Voltage forced them to use Trinity College in Ireland as a substitute. Gibson and Safinia eventually left the project, with a new director and a new screenwriter (Todd Komarnicki) taking over. Gibson and his production company Icon Productions went to court to prevent the movie from being released, claiming that they were not allowed to finish the movie, but were unsuccessful. Gibson refused to promote the film afterwards.
Mel Gibson bought the rights to the Simon Winchester book "The Surgeon of Crowthorne" in 1999, and it took 17 years for him to get it to the screen.
At the professor's first meeting with the 'Madman', he is shown to have thought he was the superintendent of the facility rather than a patient. This was a popular story at the time, but it is, in fact, false. Dr. Murray was aware of his position well before his first visit.
Dr. Minor made submissions to the OED for twenty years, and signed his submissions with "Broadmoor, Crowthorne, Berkshire." Broadmoor Hospital (the institution for the criminally insane where Dr. Minor resided), est. 1863, is located on 290 acres in the village of Crowthorne in Berkshire, England.
The score includes a haunting song, a setting of Christina Rosetti's poem "When I am dead, my dearest" (published 1862) by Bear McCreary, sung by soprano Melanie Henley Heyn.