The concept behind "Hardcore Henry" is simple, but surprisingly has rarely been explored before in film: adopt the first-person shooter POV of a video game for the purposes of a live-action feature. This is not a style that should trend—it would get old terribly fast if a cavalcade of similar movies followed suit—and yet, as a one-off cinematic experience, it is a wildly unrepentant diversion. Debuting writer-director Ilya Naishuller puts his barebones plot on the backburner in preference of a blood-spewing, limb-flying actioner managing near-ceaseless freneticism without losing its well-choreographed cohesion.

Henry has been saved from certain death, waking in a lab with a partially bionic body and no memory or voice. When the airborne facility he is in is attacked, he narrowly bolts via an escape pod with scientist wife Estelle (Haley Bennett). Once they've landed on the city streets of Moscow and Henry is separated from Estelle, the chase is on to find out who he is and what he needs to do to make it out of his ordeal. Helping him on his journey is a mystery man named Jimmy (Sharlto Copley), seemingly reincarnating himself with a different visage every time he meets a grisly end.

Primarily lensed with GoPro Hero 3 digital cameras by cinematographers Pasha Kapinos, Vsevolod Kaptur and Fedor Lyass, "Hardcore Henry" is a technical achievement above all else, told entirely from behind Henry's eyes. The editing is perhaps choppier than it should be—instead of seamlessly appearing to take place in real time, there are plenty of cuts and obvious trickery—but this does not take away from the astonishment of how certain scenes were accomplished. Because he cannot talk and his face is never seen (save for a brief partial view in a reflection near the end), Henry is uncredited among the cast list and presumably played by a cameraman and stunt person. Still, it is telling how much one is able to empathize with him simply from seeing what he sees.

If there is a standout among the actors, it is Sharlto Copley (2015's "Chappie"), whose shifting persona throughout gives him a rare chance to play upwards of twenty different people (and, cleverly, take part in a doppelgänger-filled musical number of Frank Sinatra's "I've Got You Under My Skin"). As wife Estelle, Haley Bennett (2014's "The Equalizer") beatifically represents an emblem of Henry's forgotten life rather than a fully realized character, but as more is learned about her Bennett takes advantage of the chance to stretch beyond the constraints of the role. Danila Kozlovsky (2014's "Vampire Academy") is most notable for his unkempt, bleach-blond look as the central villain of the piece, the telekinetic Akan. Akan's master plan is understandable enough, but what he is hoping to achieve from it is less clear.

A little more explanation would not have been a bad thing in helping viewers of "Hardcore Henry" unravel its convoluted narrative, though one supposes it is a testament to what kind of film it is that this murky scripting doesn't have a significant impact either way. "Run Lola Run" with severed heads and sci-fi trappings, the picture never stops moving long enough to be bothered by anything but the sheer visceral exploits on display as Henry races around, mowing down anyone who poses a threat or stands in his way of learning the truth. It's excessive. It's fearless. It's violent to a ludicrous degree, just like most like-minded video games. Based on the evidence within, director Ilya Naishuller doesn't know the meaning of subtlety, but he doesn't need to in this instance. Merciless but entertainingly auspicious, "Hardcore Henry" is what it is and makes no apologies. Adrenaline junkies not prone to motion sickness, take note.