At left, Jessica Sklar and Jerry Seinfeld attended the opening night performance of The Real Thing April 17. At right, The Ride Down Mt. Morgan's Katy Selverstone and Patrick Stewart. Tom Stoppard's The Real Thing deals with love, marriage and adultery. In shifting perspectives, couples founder and reform, and joy and passion are acutely countered by pain and deception. Stephen Dillane and Jennifer Ehle star in the revival at the Barrymore Theatre.