"Lady Murasaki" (Shikibu Murasaki) is actually the name of an 11th-century Japanese novelist. Her "The Tale of the Genji" is regarded as a masterpiece of Japanese literature. In the book on which this film is based, Lady Murasaki is indeed a descendant of the 11th-century novelist. She and Hannibal even quote "The Tale of the Genji".
Thomas Harris's source novel was released two months prior to the film's release. He had worked on it as well as the screenplay concurrently, for fear that a Hannibal Lecter prequel/origin story would inevitably be written without his involvement. Film producer Dino De Laurentiis said "I say to Thomas, 'If you don't do [the prequel], I will do it with someone else... I don't want to lose this franchise. And the audience wants it...' He said, 'No. I'm sorry.' And I said, 'I will do it with somebody else.' And then he said, 'Let me think about it. I will come up with an idea.'"
Actors screen tested for the role of Hannibal include: Hayden Christensen, Macaulay Culkin, Hugh Dancy, Rupert Friend, Dominic Cooper, Tom Sturridge, and Tom Payne.
Director Peter Webber sent Gaspard Ulliel off to a medical school in Prague to attend a real autopsy, so he could see what it's really like when bodies are cut up in order to prepare for the role. Webber thought Ulliel would be horrified, but he came bouncing into the room saying 'I've got to go back tomorrow.' Webber asked, 'Why?' and Ulliel said, "because they're flaying the skin from the body and I want to see what a flayed human body looks like." Ulliel said the lesson lasted a whole month and he came in during the last week when the bodies were all completely destroyed, and he thought that's one of the reasons why it's not that scary. It didn't feel real. The
bodies looked fake; they were so destroyed that he couldn't imagine that he was looking at a real human body, so he asked if he could go on the first day of the next session to see the fresh bodies coming in and start opening them.
The scar on Hannibal's left cheek is actually Gaspard Ulliel's real life scar. When he was six years old, a doberman was sleeping in a garden and Ulliel jumped on the dog's back and attempted to ride it a like a horse. The dog hit Ulliel with his claws, and that made a little scar on his face that looked like a dimple. Ulliel said that the scar helped to express feelings in his acting.