Remember that story about how Mr. Rogers? The one about how he was actually the most prolific sniper in the history of the Marines? (Or was it the Navy Seals?) He killed 25 (or 150) people in Vietnam and wore long sleeves to cover the tattoos adorning his arms. It wasn’t true, of course, but wouldn't that be something? We want our nice guys to have dark sides because nice guys seem mendacious. Behind that veneer of joviality something sinister must lurk. That’s what Tom Junod wanted when he was assigned to interview Mr. Rogers for Esquire in 1998; instead, the journalist, an acerbic, unsentimental writer (or, less flatteringly, a “cynic”), was startled to find out that Mr. Rogers was seemingly the real deal. Fred Rogers is portrayed by Tom Hanks in Marielle Heller’s A Beautiful Day in the Neighborhood , which chronicles Junod’s (here called Lloyd Vogel) revelatory encounter with the beloved television personality, culminating in his seminal 10,000-word essay “Can You Say… Hero?...