He strands Roland there, telling him "I could have dropped you with the sharks". David visits his long-lost mother Mary and discovers his younger half-sister Sophie (Kristen Stewart). Mary tells David that when he was five, he made his very first jump. She is a Paladin and had to either kill David or leave. After leaving her house, David meets up with Millie, and he jumps himself and her to a much warmer location. In November 2005, New Regency Productions hired director Doug Liman to helm the film adaptation of the science fiction novel "Jumper" by Steven Gould. Screenwriter Jim Uhls was hired to rewrite an adapted screenplay by David S. Goyer. However, Liman desired another rewrite and Simon Kinberg assisted in completing the script. Liman said about using the novel for developing the script: "This is 100% Steven Gould's story, it's just reinvented as a movie." In an interview, Gould revealed that he approved of the deviations from the novel. Before filming was to begin, the studio announced plans to develop a trilogy based on the novel's premise. While other films tend to use only one storyboard artist, "Jumper" required six, who each worked on an individual action sequence. The artists were given specific instruction on the rules of the teleportation used in the film, to ensure accuracy in the storyboarding. One of them, Rob McCallum, reflected on the instructions: "I was just thinking, 'How would a guy that can teleport fight?' So you were really pushing yourself to try to think of inventive, cool, spectacular ways that you could use this jumping talent that these characters have." In April 2006, actors Tom Sturridge, Teresa Palmer, and Jamie Bell were cast for "Jumper" with Sturridge in the lead role. The following July, actor Samuel L. Jackson was cast as an Roland Cox, with producer Simon Kinberg rewriting the original screenplay draft by Goyer. Principal photography was scheduled to take place in Tokyo, Rome, Toronto, and New York. Production was stopped in June 2006 after producer Tom Rothman told Liman "The lead is 18. Wouldn't the movie be better if he was 25? You have a huge movie here and adults won't go and see an 18-year-old. They'll consider it a children's movie. You could make a bigger movie than that." Liman agreed on casting older actors for furthering the romantic aspect of the film. In August, actor Hayden Christensen replaced Sturridge in the lead role as David just two weeks before the beginning of shooting, as the studio "became concerned about not having a more prominent actor in their trio of young stars."