The intrigues of such aptly named characters as Lady Sneerwell, Sir Joseph Surface, Lady Candour, and Sir Benjamin Backbite have amused theater audiences for more than two centuries. They are the invention of the Irish-born playwright Richard Brinsley Sheridan, and they unfold, collide, and backfire hilariously in his masterpiece, The School for Scandal, a play still considered by many the best comedy of manners in English. It is a comedy with two...