A decade ago, Vin Diesel was a bit of a joke. After an impressive run that included Pitch Black, The Fast And The Furious, Saving Private Ryan, Boiler Room, and The Iron Giant, Diesel began making the kinds of movies that make a lot of money despite being widely disliked, like xXx and The Pacifier. These were mistakes born of hubris: With xXx, Diesel made the mistake of trying to be the James Bond for the X Games era, when the non-extreme James Bond had been more than satisfactory for decades. 2004’s The Chronicles Of Riddick transformed the nifty stand-alone B-movie Pitch Black—a survival-horror movie with an ensemble cast and a found-family dynamic—into an ego-driven science-fiction epic, a space-age Conan solely about his unstoppable character. With The Pacifier, Diesel attempted to ape the huge successes Arnold Schwarzenegger reaped with the old “diapers + tough guy = hilarity” family-friendly formula.

Too bad Diesel lacks Schwarzenegger’s gift for both comedy and self-deprecation. He’s a lumbering, earnest, gravelly soul, and that doesn’t lend itself well to comedy. Diesel is just too sincere to cut it as a wise-ass. But by learning to embrace that sincerity, he’s scored a comeback.

Becoming a team player has helped as well. A turning point in Diesel’s career came when Dwayne Johnson joined the Fast And The Furious series’ ensemble for 2011’s Fast Five, which Diesel both starred in and produced. It was a mark of humility that the series would add someone who resembled a vastly improved version of Diesel, an actor who’s funnier, sharper, bigger, and had much more professional heat. The casting of this beloved behemoth conclusively transformed what was merely a popular series of action films into a pop-culture event.

The Fast And The Furious began as the story of Dominic Toretto (Diesel) and Brian O’Conner (Paul Walker), but the mythology grew alongside the cast with each successive sequel, until the Furious series was essentially the Mission: Impossible gang with cooler cars, or a team of James Bonds with neater gizmos. As Genevieve Koski noted in her Furious 7 review, after xXx, Diesel still got his chance to live out all his James Bond fantasies in a mega-bucks franchise filled with fast cars, faster women, cool gizmos, and nefarious, world-threatening adversaries. He just got to do it in a different series. (Although another xXx is rumored to be on the way.)

He also got to live out those adolescent fantasies in a way that feels far more organic and true to his personality than the strained attitude of xXx, particularly once the Furious cast expanded. By Furious 6, the themes were all about family and teamwork, words uttered so frequently and with such shamelessness that a drinking game could be built around them. Yet when Dominic talks about how there’s nothing more important than family and brotherhood, he means it. There’s something innately endearing about a giant pile of muscles who’s so acutely in touch with his more sensitive emotions.

But the public didn’t just re-embrace Dom. They embraced Diesel as a man and as a geek. They embraced the guy who had his tough-guy persona down pat, yet was secure enough in his masculinity to brag about his intense Dungeons & Dragons games. When Diesel predicted that Furious 7 would win the Best Picture Oscar (spoiler: It will not), the claim came across as irresistible boyish enthusiasm and pride for Walker and their team, rather than as arrogance, or a complete disconnect from reality. Diesel is seldom alone in the pictures he posts on Facebook; for him, there seems to be no real difference between the family he formed onscreen with his fellow criminals as Dom the character, and the family he formed with the actors who played those criminals. His dorky positivity is enormously winning.

Diesel is a multi-ethnic man for 2015. He has the physique of the Incredible Hulk, and the geeky psyche of a comic-book and role-playing fanboy. Diesel rapidly wore out his initial welcome with the moviegoing public through brazen acts of hubris. But he’s found his way back into their hearts both by embracing the values of teamwork, collaboration, and family, and by embodying the comics-crazed dorkiness of the current era in its most earnest, sincere form.

If anyone doubts Diesel’s underlying sincerity, I recommend checking out his Facebook account, which is full of the requisite promotional cast photos, but also effusive praise for everyone he’s ever worked with, and remembrances of Walker, whose death clearly affected him deeply. It’s easy to be cynical about his positive talk and nostalgia on social media, but Walker’s death lends them an added pathos. It’s as if Diesel has become Walker’s official mourner, the professional, permanent keeper of his flame.

At the risk of spoiling Furious 7, the film finds a curious, contradictory way to say goodbye to Walker without killing off his character, one that acknowledges the deep bond between these characters, and between the actors who’ve played them. The film ends with Diesel’s Dom delivering an impassioned speech about goodbyes that, within the film’s context, makes little sense, because within the world of Furious 7, Walker’s character is still alive. The sequence only resonates in light of Walker’s offscreen death. It should be a jarring moment, but because Diesel has been so public in his mourning of Walker, and because he invests those words with such depth of feeling, the ending is far more powerful than it has any right to be.

It doesn’t seem like a coincidence that Diesel roared back to life commercially as a fixture of two teams: in the Fast And The Furious films, and in Guardians Of The Galaxy, where he voices the sentient tree-creature Groot. It’s easy to see parallels between Groot and Diesel. Both are savvier than their wooden first impressions suggest. Both are at their best when fighting for a team they believe in. And ultimately, Groot nobly sacrifices himself for the sake of the team in Guardians Of The Galaxy. In 2015, there’s nothing hip or cool about Diesel, God bless him. He’s just a giant geek in every conceivable sense. He isn’t a more extreme version of James Bond, he’s the guy at the barbecue in a dirty undershirt with a Corona in his hand giving a treacly speech about family, and that’s the Diesel the public has come to embrace.