he show also allows the smashing Ms. Mirren to demonstrate her quick-change virtuosity in becoming the queen at different ages, from 1951 to the present, before our very eyes. Those transformations, accomplished with sleights of hand worthy of a master magician, are probably the most entertaining and satisfying aspects of 'The Audience.' It is somehow deeply reassuring to see Ms. Mirren, who turns 70 this year, step back in time as Elizabeth and persuade us that she is whatever age she wants to be. Such time-defying ease feels appropriate to the portrayal of a national ruler perceived as all but immortal.