On Monday, HBO teased its live action “Harry Potter” reboot star Dominic McLaughlin in full Potter garb. Is he destined to be the boy who flopped? 

That’s a very real possibility for a franchise that, since 2018’s “Fantastic Beasts: The Crimes of Grindelwald,” has run out of magic at the box office. 

McLaughlin’s series will adapt J.K. Rowling’s original Potter books for TV, which they are perfectly suited for. While Daniel Radcliffe’s seven blockbuster Potter films are universally acclaimed and were some of the hottest movies of the 2000s and 2010s, television allows for more faithful adaptations due to its longer length. 

That is, unless it gets mangled in Hollywood’s de facto eight-episode format. Season 1 will purportedly be eight hours long — almost the same length of four feature films — but that’s no guarantee for success. 

And for the franchise to make a comeback, it needs a smash hit. That’s because its relevance is waning. 

In the early 2000s, Potter was a cultural phenomenon. Its midnight book releases, in which lines of young people snaked out of bookstores, represented the height of the Young Adult fiction craze. That energy spilled over to its film adaptations, which were driven by a deep well of talent filled with veteran actors like Maggie Smith and Alan Rickman, as well as rising child stars — many of whom, namely Radcliffe, Emma Watson and Rupert Grint, have thriving acting careers today. 

But it all started to fall apart when series creator J.K. Rowling started tweeting about transgender people in 2019. This coincided with the spinoff “Fantastic Beasts” films, which after a strong initial entry, sputtered into irrelevancy as its sequels imploded from the worst writing in the series. 

We can debate her evolving stance on transgender people, but it is undeniable that people don’t like it when real-world politics invade their fantasy spaces. People use fandoms like “Harry Potter” to escape, not to be reminded of how awful the world is. And nobody wants to see a bad film. 

Now, “Harry Potter” is damaged goods. You can still buy plenty of its merchandise in card shops and fandom-oriented stores like FYE, but the kids who propelled it to meteoric heights are adults now, and many have moved on. “Harry Potter” is no longer one of the hottest fandoms — it’s not even a contender.

Not even slapping “Dumbledore” — a highly recognizable name of a beloved character — on the title of the last “Fantastic Beasts” movie could save it. Like Marvel, the Potterverse got itself into $400 million jail. It still has some fans, but not enough of them show up to justify chunky $200 million film budgets. That’s precisely why the franchise was kicked off the silver screen and onto the small one.

Fandoms are fickle beasts. They require constant support, stringent quality control and good marketing. Not even “Star Wars” — which survived two awful prequel films —  is immune to financial losers like its “Solo” movie. 

Fandoms can collapse virtually overnight. Move it to the wrong streaming platform, bet big on a loser script or force something people don’t want and no one will watch it. The Marvel Cinematic Universe is learning that the hard way, as its Phase 5 slate of films is filled with more misses than hits. 

“Harry Potter” can recapture its magic if it sticks to good storytelling. But it might be too late to undo the damage Rowling and the last two “Fantastic Beasts” films have inflicted on it. 

In order to stand out, it also needs to provide something fresh and innovative. A TV series whose source material already has great movie adaptations doesn’t do that. 

That leads to the series’ biggest problem: Who is this for? Is it for adult Potter fans who already have eight blockbuster movies they can watch and seven books they’ve probably already read? Or is it for the current generation, whose only interaction with Potter might be a run-in at the local library or stories from their older siblings or parents of how great this series used to be? 

This is the franchise’s last chance to prove that it still has relevance, barring a Hail Mary “Cursed Child” film led by Radcliffe and company. 

The world has changed since “The Deathly Hallows: Part 2” raked in over $1 billion in 2011, and it’s left the boy who lived behind.