"He doesn't know where he is or, for that matter, who he is. A clear mask is lowered to his mouth. The voice--a woman's--urges him, "Take a long, deep breath, and keep breathing in." The gas he inhales is warm, concentrated oxygen. It flows down his windpipe and hits his lungs with a welcome burst of heat. Though her mouth is covered, the woman leaning over him is smiling at him with her eyes. "Better?" she asks. He nods. Her face grows sharper. And her voice . . . Something familiar."