I just had my husband listen to the clip, and asked him "whose voice is that?" he had no idea. Then I told him to look at the screen and he actually startled. He thought it was an American. I really think it's pretty good (the accent, not the show).

And my daughter said "Dorothy Sayers" when I asked her to make a mystery recommendation for you. "Any Dorothy Sayers" I think those were already on your list, though, no?