Nicole Kidman has cast off her inhibitions — along with her clothes — for her London stage performance in “The Blue Room.” The Oscar-nominated actress (“To Die For”) tells Vogue that she became less embarrassed about her nakedness in the play once she realized that the nudity fit the part perfectly. “Of course, in character, I’m not even aware of it,” she said. The play is moving on to New York, where it will open Dec. 13 at the Court Theater. Kidman, 31, has received raves for her performance. She and hubby Tom Cruise have been living in London for almost two years while making “Eyes Wide Shut” for film director Stanley Kubrick.