In the series, Laurie’s Ryan uses an American accent because people apparently find it reassuring. (As an American myself, I do wonder how that could possibly be.) When things fall apart, it slips to certain people that he’s British, and he has to switch back and forth continually. When asked if that was a challenge, he says yes, but adds:
“It’s also a bit of an escape route because if you mess something up and it doesn’t sound right, you’ve always got the excuse of saying well, I’m not really [American]. That’s the whole point. I’m not really an American. That was a deliberate mistake that I put in there — which I didn’t. At all. So I found that actually easier than doing ‘House’ for example, which I just felt like it had to be right because it would get in the way if wasn’t right.”
Laurie says he’s never been comfortable with it, “not one day,” but it’s so good that … well, let’s just say that I watched “House” for years before I realized that Laurie was not in fact American.