As a friend once commented with bemused affection about an actress we adore (and I bet you do too): "It's amazing what she can do with just her voice and the 25 percent of her face that still moves."

Well, yes. A week on Monday I'm seeing a show whose impossibly-youthful above-the-title star has a very strange facial tic. When this performer speaks or sings, it appears as if their lips are somehow completely unconnected to the surrounding tissue. It is *quite* disconcerting.