How the New England Patriots evolved from a forgettable NFL franchise into the most dominant force in sports is a relationship story. It is about two men desperate to win and addicted to success once they do. They push the limits of football and of each other. They are stronger side by side but not always happier. Resentment brews, eyes wander. And after 20 mostly great years together, an old axiom prevails: All good things — even those with six Super Bowl rings — must come to an end.

The professional divorce of quarterback Tom Brady and coach Bill Belichick in early 2020 is still a buzzy topic but may ultimately be a sliver of their story, considering that each, with support from the other, became singular in National Football League history: Brady the greatest quarterback, Belichick the greatest coach, together the greatest tandem.

In “It’s Better to Be Feared: The New England Patriots Dynasty and the Pursuit of Greatness,” Seth Wickersham explores the relationship of these two men, and the role of team owner Robert Kraft, as they win at an unprecedented rate, flout rules along the way and leave 31 teams trying to replicate their success. The book also tackles a bigger question: What is the cost of greatness?

Belichick, 69, is depicted as brilliant, tireless, meticulous and ruthless. He lacks empathy and is, to put it bluntly, a jerk. “The job turned good men into ---holes,” Wickersham writes about NFL coaching, “or maybe it self-selected for ---holes.” Belichick thrives in a league in which sentimentality is a bad business model — savvy teams know better than to reward a player for past performance, and he repeatedly, dispassionately discards men who no longer serve his needs. He is the smartest man in the room, and he has complete power; now just do as he says. Belichick’s leadership style is effective but grating, particularly if exposed to it for two decades. The cost of his stern approach is the loss of relationships.

Brady, still a superstar at 44, is confident, affable and driven by slights. Those traits endured even as his personality underwent a quirky evolution, shaped in part by the unavoidable fame his success brought. He surrenders to his celebrity — not so much basking in its glow but determining that the only way to live is to dedicate himself fully to the calling that shapes his identity. He long suppressed his ego to help make his football relationships work: He took pay cuts so the Patriots could sign better players around him, and he took grief from Belichick so teammates knew that nobody was above criticism. Every choice, including the restrictive diet he adopted, was made with a 100-yard focus. The cost of his discipline was an inconsistent presence with family and friends.

And here’s where their stories diverge: Belichick calculated that even the most accomplished quarterback ever wouldn’t thrive in his 40s, so the coach planned for life after Brady, which caused inevitable strain. Meanwhile, Brady’s inner circle nudged him to reconsider his life’s balance. What’s more important — the relentless pursuit of the next ring or an overall healthier existence? Brady decided he could simultaneously achieve both, but not under Belichick. In March 2020, Brady signed with the Tampa Bay Buccaneers and then led them to a Super Bowl victory.

Wickersham elegantly demonstrates the grander themes at work after watching them play out from the start. A former high school quarterback from Alaska, his first job out of college in 2000 was at ESPN the Magazine. About a year later he was assigned to profile the Patriots’ quarterback, who, like Wickersham, was a 24-year-old just trying to make it in the game.

As an NFL reporter in search of the league’s biggest stories, Wickersham found that his GPS repeatedly pointed in the direction of Foxboro, Mass. Not only were the Patriots successful, they were scandalous. They ran afoul of league rules in 2007 when they videotaped an opposing team’s signals and then again in 2015 when they reduced the air pressure in footballs. Later in 2015, Wickersham and fellow ESPN senior writer Don Van Natta Jr. reported how the league’s harsh discipline of the Patriots for “Deflategate” was, in one owner’s view, making up for the light treatment they received for “Spygate.”

The 21st-century Patriots started off as charming underdogs but became less endearing the longer they reigned. Brady, Belichick and Kraft’s ambiguous support of Donald Trump before the 2016 election polarized them further. When Belichick wrote a glowing letter to Trump, and the eventual president read it at a campaign rally, the coach’s explanation to his team was uncharacteristically insincere. It’s the type of incident that could divide a locker room, but players who disapproved of Belichick’s politics were afraid to take a stand, Wickersham writes, because it might have jeopardized the one thing that mattered most in their building: winning.

The book consistently delivers that type of fly-on-the-wall access, taking the reader to seemingly impenetrable places, such as when:

Belichick’s mentor, Bill Parcells, tells his protege he’ll never make it as a head coach.

Kraft confides to friends that Belichick is “the biggest f---ing ---hole in my life.”

Brady, as a rookie, runs naked on his condo’s lawn as penance for losing a video game.

Brady, as a veteran, sheepishly carries his wife’s dog into work in a handbag (yes, Gisele Bündchen’s Yorkie — in a Louis Vuitton).

Reporters have breathlessly covered the Patriots over the years, leaving little room for new reveals, but Wickersham advances the ball with anecdotes that unpeel the personalities of the franchise’s significant figures. He also adds nuance to long-discussed topics among Patriots fans.

A common barroom debate in New England is who’s more responsible for the franchise’s success — Belichick or Brady. It’s an impossible hypothetical, but over a round of Harpoon Octoberfests, it’s bound to bubble up. Brady’s championship in his first NFL season away from Belichick may have swayed many to his side. Belichick, now with his handpicked quarterback, rookie Mac Jones, will get a chance to even the score, though this season’s start has not been very promising.

In “It’s Better to Be Feared,” Wickersham does not attempt to answer the unanswerable but instead aims to chip away at Brady and Belichick from a more existential perspective. The book, he writes in its prologue, is about “understanding the Patriots’ greatness and the larger idea of greatness itself — what they traded for it, what they received in return, and what ultimately they sought but did not find.”

It’s Better to Be Feared

The New England Patriots Dynasty and the Pursuit of Greatness

By Seth Wickersham

506 pp. $30