My Fair Lady, the theater historian Ethan Mordden writes, “is still regarded by the public at large (if not the historians and aficionados) as the greatest of the great musicals. Or is it just the greatest hit in the history of hits?” Whether one or the other, a revival is always an event. This is the touring version of the award-winning Lincoln Center revival, directed by Bart Sher, which opened to raves. It features Shereen Ahmed as Eliza Doolittle, Laird Mackintosh as Professor Henry Higgins, and Leslie Alexander as Mrs. Higgins —L.J.