I adore Sherlock Holmes. There is a strong case to be made that he is my favorite fictional character. He certainly sets the template for my favorite type of character: the eccentric genius. I also love adaptations of Sherlock, and the Sherlock lore, so when I heard that Netflix was releasing a movie about Sherlock’s heretofore-unknown sister, I was intrigued.

Enola Holmes is based on a series of Young Adult novels by Nancy Springer, and stars actress Millie Bobby Brown, of Stranger Things fame, as the titular Holmes sibling. We first meet Enola on her sixteenth birthday, en route to the train station to meet her brothers, the famous Sherlock (Henry Cavill), and somewhat less famous Mycroft (Sam Claflin). Speaking directly to the audience, Enola explains that they’ve come from London to investigate the disappearance of their mother- and to this point Enola’s only caretaker, teacher, and friend—Eudoria (Helena Bonham Carter).

Enola is a winning character, plucky and clever—and a little naive—and she is played with great charm by Brown. Her performance is hands down the best part of the movie. Coming in second is Cavill’s Sherlock, a slightly less neurotic version of the character than what we’ve been seeing on screen or TV lately. Helena Bonham Carter is as reliably good as always, although the role is yet another entry on her huge list of oddball characters. At this point I’d be fascinated by the novelty of seeing her just playing a banker or something.

The plot is kicked off by Enola’s simultaneous desire to solve the mystery of Eudoria’s disappearance, and her need to escape from Mycroft. The Mycroft of this film is, interestingly, not as intellectually gifted as his younger siblings, and resentful of that fact. This is a change from the canon, but it adds a compelling dimension to his relationship with the other Holmeses.

Victorian priss that he is, Mycroft cannot abide the “wild child” living in what is, technically, his house. Thus, he arranges for Enola to be matriculated at Mrs. Harrison’s Finishing School for Young Ladies. Enola’s wish to avoid this fate sends her fleeing to London, and headlong into the second mystery of the film, involving the runaway young Lord—and ostensible love interest—Viscount Tewskbury (Louis Partridge).

Typically, a mystery film lives and dies by the quality of its mystery, and the ingenuity in the solving of it. In this movie, the two central mysteries—the missing mom, and the runaway Lord—are only so-so. Anyone paying even the slightest attention will connect the necessary dots. But this is less Agatha Christie-style puzzle movie and more young adult adventure film, and on those terms, it’s… fine.

Enola is, as I said, a dynamic and compelling lead. The directing, by veteran TV director Harry Bradbeer, is competent, but lacking in flair. Much of the movie does, in fact, feel like a long pilot episode to a TV show. The film also tends to underline its feminist themes in a way I found heavy-handed, though the most noteworthy line does come out of this, delivered by Susie Wokoma, as Edith, a Victorian-era martial arts master and real person: “Politics doesn’t interest you because you have no interest in changing a world that suits you.”

Most disappointing is the bland love story. Though it’s connected to one of the two central mysteries that Enola is investigating, it still somehow manages to feel shoehorned in. Perhaps this is because of Partridge’s Tewkesbury, who never really develops a personality beyond his haircut. Every minute Enola spent working on his case, I wished she was hunting her much more interesting mom.

Fortunately, far and away the most time is spent with Enola herself, and her presence is engaging enough to compensate for much of the movie’s other flaws. In particular, scenes between Enola and Sherlock really sing; Brown and Cavill have great chemistry as brother and sister spar and slowly get the measure of each other. I would buy into a sequel if it promised more of these two working together.

Enola Holmes is not a great film. As a Sherlock-adjacent property, I was definitely hoping for a little more mystery-solving than what I got. However, it is still a perfectly adequate YA adventure flick, carried by Millie Bobby Brown’s charismatic central performance as Enola. Younger viewers should find her a compelling heroine to root for, and older Sherlock fans will find an interesting new member of the family to fan over. Here’s hoping the likely-inevitable sequel gives Ms. Brown a story that’s more on her level.

Final score: 3 out of 5 Prissy Victorians