The script was not completely prepared when filming began, since the filmmakers were more focused on the story and the action, so the dialogue was mostly ad-libbed throughout filming; Jon Favreau acknowledged this made the film feel more natural. Some scenes were shot with two cameras to capture lines improvised on the spot; Robert Downey Jr. would ask for many takes of one scene since he wanted to try something new. Gwyneth Paltrow, on the other hand, had a difficult time trying to match Downey with a suitable line, as she never knew what he would say.
