Millie Bobby Brown was called upon to be wise beyond her years in her indelible portrayal of the troubled Eleven in "Stranger Things," solving puzzles that were both mentally and physically difficult, and providing a clear path forward in a dark and confusing world.

As the title character in “Enola Holmes, ” Brown must shoulder all those responsibilities again — only this time, she gets to have a complete blast doing it. Brown is nothing short of radiant here, exhibiting the same kind of mature presence and poise we've seen in the sci-fi series on Netflix, but also an entertaining fun side and impeccable comedic timing.

It is like meeting her all over again for the first time, and it is a pleasure. And if the way “Enola Holmes” ends is any indication, this may be the start of a most welcome girl-powered franchise.

"Enola Holmes" sees Sherlock's younger sister stirring up trouble, solving mysteries and carving out her own place in wealthy Victorian England, based on the Young Adult novel series by Nancy Springer. She's very much her own person in the way she plays the detective, despite having a famous sibling.

Emmy winner Harry Bradbeer brings to this stuffy environment an infectious energy by making Enola crack the fourth wall from the get-go with amusingly self-aware asides, a technique he often used on the many "Fleabag" episodes he directed.

She stares squarely into the camera and speaks to us as she rides a bicycle through rolling hills and large fields of flowers, that is, before she bites it and falls in the dirt face-first. "Cycling is not one of my main strengths," as she dusts herself off, and we are hooked, she explains matter-of-factly.

In the script from Jack Thorne, Enola notes that her name is “alone” spelled backward. And she and her thoroughly unorthodox mother (a well-cast Helena Bonham Carter) are exactly that as they prowl about their expansive country mansion doing whatever they please: painting, reading, even playing tennis and archery indoors. (As the coolest homeschool teacher ever, Carter is an inspiration to all us struggling parents.) But then she disappears suddenly as Enola turns 16, leaving her daughter to fend for herself with a series of cryptic clues and a couple of disapproving older brothers who’ve returned to check on her.

Henry Cavill is the hunkiest Holmes ever—truly, it’s hard to imagine how he found time to hit the gym between solving crimes—and Sam Claflin literally gets a mustache to twirl as the snooty, scheming Mycroft. But while Sherlock seems to appreciate his little sister’s sharp mind and spry demeanor, Mycroft is mortified by how unkempt and uncouth she’s become, and insists on sending her to an uptight finishing school to turn her into a proper lady. (Fiona Shaw is straight out of a Dickens novel as the prim and persnickety headmistress.)

“I don’t want a husband,” Enola informs Mycroft with conviction. “And that is another thing that will have to be educated out of you,” he responds, in what will come to define the film’s true central conflict: the fight for female liberation in a patriarchal society that’s loath to evolve. But while it takes place as legislators are considering women’s suffrage and Enola’s battle cry (handed down from her forward-thinking mother) is “Our future is up to us,” the film as a whole is mostly a light, family-friendly adventure, filled with secret codes to decipher and hidden treehouses in the woods.

When Enola travels by train to London to hunt down her mum, she ends up running into and inadvertently rescuing the Viscount Lord Tewksbury, Marquess of Basilwether (Louis Partridge), who happens to be an escaped teenager, just like her. And just like her, he doesn’t want to follow the posh path his family has laid out for him. With his dark, floppy hair and sly smile, the appealing Partridge has a young Mick Jagger vibe about him, and he and Brown share a sprightly, hyper-verbal chemistry.

London through the eyes of cinematographer Giles Nuttgens (“Colette,” “Hell or High Water”) is an imposing, crowded cesspool of chaos, a sharp contrast from the lush colors and warm sunshine of the countryside. Here is where “Enola Holmes” really begins to feel like two movies functioning side by side, mostly in concert with each other.

Enola is still searching for her mother—and along the way, finds a badass underground of women fighters, led by Susan Wokoma’s formidable tea shop owner/jiujitsu trainer.

But she also wants to protect Tewksbury from the dastardly forces insistent on putting him in his place, and get to the bottom of why he’s in danger. Brown’s charismatic presence goes a long way toward helping sew up these storylines neatly, as do Adam Bosman’s editing and Daniel Pemberton’s lively score.

At over two hours, “Enola Holmes” does run a bit too long, though. It also turns weirdly violent toward the end in a way that’s a jarring shift from the adventures we’d enjoyed previously, which were only kinda-scary at times.

But hopefully Brown—as both star and producer—will continue solving mysteries in England between seasons of solving mysteries in Hawkins, Indiana.

Now available on Netflix.