DEAD RECKONING

At the Sphere, a fan wrestles with what the Grateful Dead have left behind.

- NICK PAUMGARTEN

Dead & Co. have made the band perhaps bigger than ever, or at least broader.

In May, I came across an ad in the subway promoting the months-long residency at the Sphere, in Las Vegas, of Dead & Company, the current permutation of the Grateful Dead, featuring two surviving members, Bob Weir and Mickey Hart, and the pop star John Mayer. The ad read, in a brassy "Star Wars" font, "Dead Forever." I remembered what David Letterman said years ago when he saw a billboard in Times Square for the musical "Cats": "Cats: Now and Forever-is that a threat?"

And yet, a month later, I found myself on the way to Las Vegas, where the band was a dozen shows into thirty at that glimmering new Sno Ball of a hall just off the Strip. Half the seats on the flight seemed to be occupied by fellowDeadheads, identifiable, as ever, by the hieroglyphs. I had checked no luggage, but I carried some personal baggage. It had been forty years, almost to the day, since I’d caught my first Grateful Dead show. The week of my flight, an elderly evangelist in a sun hat had stopped me in Central Park and asked, “Young man, what makes you happy?” I paused, then exclaimed, “Jerry Garcia!”