Apart from mistaking energy for exhilaration, the movie is a mostly flavorless puree of dark humor, comic-book sentimentality and ultra-bloody combat. But it’s the relentless and banal video-game aesthetic that may get you involuntarily reaching for a controller in hopes of finding a pause button.

Wasting no time — because who needs background or mood? — Moritz Mohr’s feature debut drops us in a totalitarian post-apocalyptic world just when, as part of a televised ritual called the Culling, a little girl in a pink onesie is shot in cold blood by grim-looking, black-clad Hilda Van Der Koy (Famke Janssen), matriarch of the sadistic family running this tyrannical land. This future indeed looks horrible. Cut to the girl’s surviving brother, now an orphan being raised over the years in the art of punch-stab-and-kick vengeance by a wild-eyed shaman whom action aficionados will recognize as Yayan Ruhian from the legendary “Raid” movies.

Comedy nerds will pick up that it isn’t Skarsgård narrating his own deaf-mute character’s inner thoughts but rather animation stalwart H. Jon Benjamin (“Archer,” “Bob’s Burgers”). A post-completion revision (early screenings featured Skarsgård‘s voice), it’s a tonally jarring choice, since Benjamin’s winking cockiness can’t make lines like “I am an instrument of death” sound serious, and even when laughs are intended in the dippy screenplay by Tyler Burton Smith and Arend Remmers, they fall flat. Though explained as the Boy appropriating his favorite arcade game hero’s voice, the running commentary plays like an open mic-night reject hijacking a B movie.

Famke Janssen in the movie “Boy Kills World.”

(Roadside Attractions)

Mohr is considerably more invested in the gory melees, each goon-vanquishing level getting Boy closer to the Van Der Koy compound and the Culling program’s vicious architects: Hilda’s show-producing sister Melanie (Michelle Dockery), her TV host husband (Sharlto Copley) and brother Gideon (Brett Gelman). Each baddie’s shouty, smarmy performance seemingly exists only to be wished a violent end, yet Copley — an old hand at over-the-top villainy — is at least watchable, as Lee Van Cleef and Jack Palance were in their love-to-hate heyday.

The exhaustive fights, coordinated by Dawid Szatarski and which include nightmarish use of a cheese grater, are designed in the extended-play style that “Oldboy” dynamically ushered in. (Now it’s ubiquitous and outlandishly effects-enhanced, as seen in this spring’s “Road House” and “Monkey Man.”) There are differences, of course, and Mohr’s bag-of-tricks approach hews closer to the merry-go-round artificiality of “Kingsman” director Matthew Vaughn than the modern-dance muscularity perfected by “John Wick” helmer Chad Stahelski.

For those preferring choreography and performance to a lookie-lookie director armed with a drone, “Boy Kills World” will disappoint, even as the music by Ludvig Forssell and El Michels Affair provides suitably thumping accompaniment.

So why overdo it? The shame is that “John Wick 4” alum Skarsgård, when not sharing time with that ridiculous voice-over, is not only a commanding mayhem machine with his lanky physique and those intense eyes but also occasionally a compellingly naïve figure, even if Boy’s sleeveless red top can sometimes make him look like an ’80s music video extra. But he’s ultimately more a game piece than anything else.

As the climax with a helmeted assassin (Jessica Rothe) draws near, there is one admirably unforeseen twist up the film’s blood-smeared sleeve. I’m not sure it’s a good thing, though, that it takes so long to get there. For this boy to kill the world, the movie shouldn’t need to kill our patience first.