He won an Oscar for playing a monarch trying to overcome a speech impediment, and now it looks as if Colin Firth will do a role in which he tries to get a street urchin to speak beautifully. I’m talking about the remake of “My Fair Lady,” of course, which has been scripted by Emma Thompson and will star Carey Mulligan as the urchin Eliza Doolittle. The Firth role, of Henry Higgins, was apparently offered to Hugh Grant, who turned it down. (Which leads to the question: unless he’s retired from the business, just what the hell else has Hugh Grant got going these days?) My dream casting would have been “House”‘s Hugh Laurie, whose long-ago affair with Thompson apparently wasn’t good enough to boost his chances. (He’s perpetually busy with “House,” anyway.) Firth’s casting isn’t final yet, but I suspect that it will be soon.