When Show Boat opened on Broadway in 1927, it was an instant hit. Now, as co-music director and orchestrator of Show/Boat: A River Dan Schlosberg said, “People don’t want to touch it.” Show/Boat: A River, directed by David Herskovits, founding artistic director of Target Margin Theater, reexamines Show Boat as a deeply flawed piece of Americana. For much of the 20th century, Show Boat endured as a beloved classic, thanks to a lush, romantic score by Jerome Kern and Oscar Hammerstein II. In recent years, the show’s dated treatment of race has made revivals all but untenable . Show/Boat: A River , now running in the experimental theater festival Under the Radar , marks the show’s return to New York after 30 years. Herskovits’s adapation seeks to celebrate the material’s beauty while dissecting its ugliness and holding it up to light. Although I am a person with an alarmingly robust knowledge of musical theater, I barely knew Show Boat before I started reporting on it. I knew song...