FOUR MONTHS before the season devolved unexpectedly into chaos, the extended Boston Celtics franchise gathered in a theater to celebrate yet another championship. I checked in at a small table and went inside, just a few blocks from the Brahmin church where Bob Cousy eulogized John Havlicek, and from the four-star hotel where Red Auerbach lived. I’d been immersed for months in the Boston basketball history lurking all around the city, no artifacts more wreathed in meaning than the living human beings who witnessed that history and, in a few cases, created it. Tonight’s party was a high table meeting of those witnesses and high priests. An old magic made the room crackle. Bill Russell’s daughter, Karen, looked regal in a flowing outfit, as she caught up with the Boston press corps. Jayson Tatum and Jaylen Brown held court. Jackie MacMullan introduced me to Celtics guard Jrue Holiday. Dan Shaughnessy and his wife milled around near the bar and 1981 Finals MVP Cedric Maxwell found a little bistro table and settled into a chair. “The connection is family,” Red Auerbach’s youngest daughter, Randy, said. “It’s part of our DNA.”

The occasion this snowy Friday evening was the premiere of Bill Simmons’ HBO documentary series, “Celtics City,” which tells the history of Boston through its basketball team. Sam Cassel, who won a title as a backup guard in 2008 and another last season as an assistant coach, shook hands with different generations of players and staff.

“This is a lifestyle!” he said later. “Being a Celtic is a lifestyle!”

The 2024 Larry O’Brien Trophy, polished to a high shine, stood on a pedestal in the middle of the party. Nobody was too cool to cherish the moment. Even owner Wyc Grousbeck took a picture. The party was a celebration of last season’s glory, even as the current team tried to focus on winning a second title in a row. Tatum is the chief inheritor of this core Celtics dilemma; he must remember the glorious past but also stay focused on the future. Professional athletes like Tatum radicalize the present, looking to sculpt such a bright future that their name might live forever. But athletes who chase that dream in Boston find themselves in a tricky opportunity trap. Tradition is life-giving, yet also comes with burdens. When Bob Cousy retired, Bill Russell said his memory was now their opponent, every bit as much as the Lakers, and he meant it.

When Grousbeck bought the Celtics in 2002, he found this subculture torn apart by Rick Pitino, who’d demoted Red Auerbach as team president. One of the first things Grousbeck did was get on a private jet to fly down to D.C., where Auerbach lived, and bring him back as team president. For more than two decades, Grousbeck has managed the team with a simple philosophy: What would Red do? He shaped the team’s future, and earned two titles, by looking to the past. All that was ending this season. His father was 89 years old, a pioneer of private equity, and apparently, the family needed to unload the team, Grousbeck’s pride and joy, for estate planning purposes. Uncertainty mixed with revelry as last season’s glory transitioned to this season’s quest. You could feel the shifting sands as the first game approached. New owners would be coming in. Because of the NBA’s new collective bargaining agreement, which is designed to guard against dynasties, the clock was ticking on the current team, which had been to two Finals and won one. In the foyer of the theater, Grousbeck saw an older man standing near the trophy and went to pay his respects. It was Mal Graham, a retired state judge who, in a previous life, won two titles with the Celtics. Grousbeck and Graham laughed and compared the size of their jewelry. Grousbeck’s is from 2024. Graham’s is from 1969. They touched rings like superheroes trying to join forces.

“Last back-to-back,” someone standing nearby whispered to me. That came as a surprise. The Celtics, whose mythology is rooted in the idea of a forever dynasty, have not won consecutive titles since 1969, Bill Russell’s final season. Nine different teams have repeated since the Celtics last went back-to-back 56 years ago: the Lakers, the Pistons, the Bulls (twice, with threepeats), the Rockets, the Lakers (with a threepeat), then the Lakers again with two, then the Heat and finally the Warriors. Winning multiple consecutive titles is at the core of the Celtics’ mythology, but Larry Bird and Kevin McHale tried and failed. Jo Jo White and John Havlicek tried and failed. Kevin Garnett and Paul Pierce tried and failed.