His castmates in Band of Brothers (2001) were initially skeptical of how well he could handle playing an American. It turned out that he was so convincing (as an American) that some cast and crew didn't believe he was British.
If one of your fantasies is lying on a bed in Hollywood, surrounded by
eight naked women, then another is to have a beautiful wife and a nice
rambling house in London with three kids running around... perhaps it's
good to have a bit of tension in your fantasy life.