Perhaps the greatest compliment that can be paid to “Fantastic Beasts and Where To Find Them” is that it falls perfectly into the magical “Harry Potter” mythos built by J.K. Rowling, yet it remains its own story.

Oscar-winner Eddie Redmayne plays Newt Scamander, a character briefly mentioned in the Potterverse as the author of the textbook “Fantastic Beasts and Where to Find Them.” He’s front and center here, having arrived in New York City in 1926 with his oversize briefcase and a covert mission. Newt is a magizoologist, and in his briefcase he’s carrying all sorts of magical creatures — fantastic beasts, if you will — with the plan of returning one to its natural habitat in America.

It’s a troubling time in the magical world, with an evil wizard, Gellert Grindelwald, missing and anti-magic protesters holding demonstrations on the streets. Newt gets caught up in all of this, teaming up with former Auror Tina Goldstein (a strong Katherine Waterston); her sister Queenie (Alison Sudol, in full flapper mode), who can read minds; and No-Mag (what the Brits call a Muggle) Jacob Kowalski (Dan Fogler).

The rich, dense story, written by Rowling herself (making her debut as a screenwriter), unfolds like a good mystery. It’s a familiar vocabulary: magical spells, quirky, playful characters and a complicated magic-political structure — here the MACUSA, the Magical Congress of the United States of America.

This is also more of a street level film, using the grittiness of the 1920s New York City setting — fully recreated at a studio in London. Without an enclosed location like Hogwarts, “Fantastic Beasts” really has room to breathe, be it on the city boulevards and in the subway stations, or even within Newt’s magical briefcase.

Director David Yates — who helmed the last four “Potter” films, not to mention “The Legend of Tarzan” earlier this year — was faced with a difficult task. He had to create a movie that would appeal to a feverish fan base, not feel like just a ninth “Harry Potter” flick, while opening up a new franchise that is slated for five installments of its own. “Fantastic Beasts” achieves that goal, offering its own unique sense of wonder and terror, which come from the more grounded approach and real-world setting.

The cast is also superb — not surprising from the cavalcade of superstar U.K. actors in the “Potter” films. Newt has some of the awkward charm of Daniel Radcliffe’s Harry Potter, but Redmayne imbues that with a gentleness you’d only find from someone who genuinely cares for animals. Fogler’s Jacob, who takes on the comic relief role, is the kind of lovable, endearing character that Rowling seems to excel at creating. And Sudol’s innocent and sweet Queenie could have been plucked straight out of celluloid history.

And then there are the fantastic beasts. There are many of them in the film, from tiny troublemakers to large, majestic creatures, and they play an integral part in the plot. The “Potter” films were filled with unique animal life, but this film takes it to the next level. And even the most outlandish of the critters are handled well, which is certainly a testament to the skillful effects team.

Considering that a ticket for the play “Harry Potter and The Cursed Child” on London’s West End is about as tough to score as one for “Hamilton,” and the screenplay was a bestseller, “Fantastic Beasts and Where to Find Them” is pretty much critic- proof. Even if this was a debacle, it would still do huge numbers at the box office.

But this is no debacle. It’s a superb, magical adventure and the perfect reset button for this franchise.