It’s nice to know that some tried-and-true movie rules have survived the streaming resolution. For example: If two or more people are climbing a mountain together in the first scene of a film, at least one of them won’t live to see the title card (see: “Cliffhanger,” “Vertical Limit,” “The Living Daylights,” etc.). So it goes in Baltasar Kormákur’s “Apex,” a rope-thin but gnarly enough Netflix thriller that opens with Sasha (Charlize Theron) and her extremely doomed husband (Eric Bana) scaling Norway’s famous Mt. CGI before tragedy rains down upon them like a ton of rocks. His demise is a foregone conclusion from the moment he suggests that his days of sleeping in a bivouac several thousand feet above the ground might be coming to an end — a suggestion that Sasha interprets as a surrender. Some people don’t feel alive unless they’re staring death in the face, and I suppose that she must be one of them. 

It’s hard to say for sure in the context of a genre exercise so threadbare that it feels like it might snap under the weight of a single character detail — much like the cord that Sasha had to cut in order to save herself from being pulled off that Norwegian mountain along with her late husband. Still, we can probably intuit as much from the fact that she grieves her loss by embarking on a solo kayaking trip in the Outback. While Australia’s foamy little rapids may not be thrilling enough to shock our heroine out of her guilt, or her sadness, or whatever unspecified emotions she happens to be traveling with, the challenge of surviving a psychotic hunter named Ben (Taron Egerton, his jawline never sharper) who preys on hapless vacationers should be able to get the job done. Man, it turns out, is but the second-most dangerous game, even if Ben considers his pursuit of Sasha to be more of a ritual.

It’s hard to say if Jeremy Robbins’ script takes a clear position of any kind on Sasha’s lifestyle, but its psycho killer — who gives his prey a headstart the length of The Chemical Brothers’ rave anthem “Go” before he starts to hunt them down — certainly taunts her for it. “What’s the matter,” Ben asks of his next victim as her eyes bulge with terror, “I thought you liked danger?” Maybe it’s not as fun when you have to confront it alone. Maybe she doesn’t get the same high from surviving life’s extremes without someone who can bear witness to and reflect her own accomplishment. Maybe, to paraphrase her late husband, Sasha just needs a partner to help straighten her out whenever she’s lost the plot.

Ben probably isn’t who her husband had in mind, but it sure feels pointed that Sasha and her stalker are bound quite literally bound together at a certain point, as if to suggest that nothing in this world exists in a vacuum. A mountain summit can’t exist without its foothills, an apex predator can’t be defined as such without its prey, and Sasha, I guess, can’t reassert her vaguely defined reason for being without the absolute madman who’s trying to add her head to his mantle.

The truth of what Ben does with his kills is actually a fair bit more fucked up than that, which is a major blessing in the context of an undernourished survival movie that needs every iota of meat and flavor that it can find. Egerton makes a full meal of his role, credibly scaling the character from “questionable expat” to “Norman Bates-level psychopath” with just a twitch of his neck; the details of his insanity are best left unspoiled, especially since the film’s story is short on meaningful details, but it’s safe to say that it feels a bit rich for Ben to suggest that Sasha’s mental wiring is messed up. Never trust a man who names his beef jerky after his mom (or, for that matter, a man who names his beef jerky after anyone). 

It would have been asking too much for Ben’s childhood wounds, such as they are, to accentuate the fresher ones that Sasha brought with her to Australia, but with so little else to hang onto I couldn’t help but try to read a bit deeper into how these characters rhyme with each other, especially since Egerton is so game to go nuts, and Theron — ever the reliable action star, radiating strength through a clenched vulnerability — is as human as he is cartoonish. This decent but disposable Netflix programmer doesn’t have any real interest in being watched along those lines, but Kormákur doesn’t seem particularly engaged with the rugged survival action either, and it’s not a coincidence that the setpieces don’t start to pop until they begin to assume a more conceptual bent.

So it goes in a movie that has no ambition to be the apex of anything, but also manages to avoid rock bottom.

Grade: C

“Apex” starts streaming on Netflix on Friday, April 24.

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