Netflix does halfway decent Dahl

What’s better at Christmastime than watching a group of petrified children being called “maggots” by their cruel teacher?

The big bad bully under the tree is Miss Trunchbull, from the dark mind of British author Roald Dahl, in Netflix’s all-right adaptation of “Matilda the Musical.”

Australian composer Tim Minchin’s show — whip-smart if somewhat frigid — ran on Broadway for four years and continues to play in London, and onstage the distinctive musical has a sickly, subversive, nuclear sludge-like atmosphere shrewdly broken up by the occasional sweet song sung by little kids.

Audiences love nothing more than watching a pack of perky preteens sing and dance.

The lesser film version, directed by Matthew Warchus who also helmed the live musical, is unfortunately absent of any invigorating aesthetic to rouse viewers. The movie looks like every other Netflix show shot in Britain — “Sex Education,” “Heartstopper” — except that here children break into song on unremarkable cobblestone streets.

Stage directors, by and large, are inept at making movies and yet we keep allowing them to make movies. Still, “Matilda” has her moments.

Matilda Wormwood, played by the adorable Alisha Weir, is a brilliant mind and voracious reader who was born to two negligent idiot parents (Andrea Riseborough and Stephen Graham, not getting enough laughs). They ignore and resent their daughter, so she finds solace in novels and making up imaginary stories.

One tale that she tells a friendly traveling librarian, Mrs. Phelps (Sindhu Vee), is the dramatic circus romance of an acrobat and escapologist. This tacked-on side plot, which weaves into the action later on, stops the movie dead in its tracks. It’s boring and hard to follow.

“Matilda” is more madcap and enjoyable during the scenes at Crunchem Hall school, lorded over by the vicious Trunchbull (Emma Thompson), an imposing woman and former competitive hammer-thrower who loathes sniveling children. The tykes she particularly can’t stand get locked in the “chokey,” a dangerous wooden locker in the forest, or swung in the air by their pigtails.

While there is some guilty pleasure to be had in watching Thompson transform into the hulking villain, I missed when the role was played in drag on Broadway by the far funnier Bertie Carvel. Thompson is more tickling than hilarious.

Matilda’s adult ally at school is Miss Honey (Lashana Lynch), an angelic teacher who adores her students, much to the chagrin of her horrible boss.

A useful aspect of watching the movie on streaming rather than onstage is you can turn on the subtitles to catch all of Minchin’s clever lyrics. Many of the quirky phrases, coming fast and furious, were muffled on Broadway and the score improved when I listened to the album later. You won’t be humming anything after, however. No “Chokey With the Fringe on Top” here.

The best songs are the slow and pretty “When I Grow Up” and “Revolting Children,” which has a decent hook and spirited choreography from Ellen Kane.

“Matilda” is not the worst Dahl movie adaptation by a long stretch. The most recent version of “The Witches” starring Anne Hathaway was miserable and embarrassing. But if you really want to give the kids a spook and a very fine film, put on Nicolas Roeg’s 1990 “The Witches.” I’ll take Anjelica Huston’s frightening, eccentric, committed Grand High Witch over Thompson’s mediocre Miss Trunchbull any day.