Back in 1975 actor L.Q. Jones made a screen version of “A Boy and His Dog,” the 1969 novella by the late, lamented Harlan Ellison in which a young man named Vic and his telepathic dog Blood struggle to survive in a post-apocalyptic American Southwest; the cynical dystopian movie has become a cult classic. Now Albert Hughes offers a tale of human-canine bonding from the opposite end of the chronological spectrum, reaching back some twenty millennia to speculate about how a sensitive teen named Keda (Kodi Smit-McPhee), left for dead during a hunt, allies himself with a wolf (played by a dog named Chuck) that he’s injured but nurses back to health. As they work together to get Keda back home, the result is the beginning of the domestication of canines; before it’s over, Keda has given his new best friend a name, Alpha (though nitpickers might wonder how exactly he came up with the first letter in an alphabet that won’t be invented for many millennia—or why some other characters are called by Greek letters, either), and has even accidentally taught it to fetch.

The tone, of course, is very different from Jones’s film: though it features plenty of physically harrowing scenes, “Alpha” at bottom has the DNA of an old-fashioned Disney live-action adventure movie: ultimately it’s sweet, sappy, and for dog lovers probably irresistible. Whether it’s suitable for very young kids is another matter. The dialogue is spoken in some archaic tongue, and subtitled, which isn’t exactly toddler-friendly. And some of the sequences might be awfully scary for youngsters.

One thing that can be declared with absolute certainty, though, is that the picture is visually spectacular, with the combination of awesome Canadian locations and CGI enhancement often astonishing, especially when seen on an IMAX screen (with the optional addition of 3D, well used in several scenes).

That applies not least to the opening sequence, in which Keda, having been one of the few to pass the test in arrowhead-carving presided over by his father Tau (Jóhannes Haukur Jóhanneson), the tribal chieftain, goes off on his first communal hunt, despite the concerns of his mother Rho (Natassia Malthe) that the boy is too tender-hearted to meet her husband’s demands.

The actual hunt takes place after a long trek, marked off by rock structures left as signposts by “the ancestors,” with the tribesmen using their spears to chase a herd of bison toward a dizzying high cliff, hoping to force them over so that they can then butcher the carcasses. Unfortunately Keda is targeted by one of the animals, which hurls him (in slow motion) over the edge; he lands on a ledge hallway down the sheer face of the mesa, unconscious and perhaps already dead. Unable to reach him, Tau must perform what amount to the last tribal rites—building a small pile of stones—and lead his people home.

But Keda eventually awakens when a vulture arrives to feed on him, and after struggling for a while to climb down, falls to the ground, surviving yet again but damaging his leg in the process. After contriving a makeshift splint, he undertakes the long, arduous journey home with little but grit on his side.

His meeting with the wolf he’ll call Alpha is not initially friendly. The wolf pack forces him to take refuge in a desiccated tree, and with a lunge he wounds one of the animals, which falls as the others leave. The boy has some trouble tending to the wolf’s wounds without getting his hand bitten off, but manages, and then gingerly offers it some water and food. The wolf attaches itself to Keda, and in time will return the favor, rescuing the lad on several occasions at risk to itself.

The two will have to battle the elements—thick snow cover and ice—as well as other predators like hyenas and panthers (one of which carried off a boy Keda’s age, called Kappa and played by Spencer Bogaert, in the film’s initial reel). They will also learn to hunt boars together, with the wolf chasing them toward the boy, who wields his spear more and more efficiently with practice (Alpha also shows an aptitude for catching fish). There are occasional amusing interludes, as when Keda insists that the reluctant wolf bathe in a lake with him or struggles to follow his father’s example and get a fire going, but most of the time the narrative concentrates on the brutality of the journey, with one especially grim scene showing the fate of a human trapped in the cold without food. (For some Sandra Granovsky’s editing might seem a bit sluggish, but the movie clocks in at only a bit over ninety minutes.)

Eventually, however, the two reach the tribal camp, where they are both warmly received by Keda’s parents, and where the wounded wolf, tended by the group’s shaman (Leonor Varela), has a last secret to reveal—one designed to draw a chorus of contented “awws!” from viewers young and old. You really didn’t think it would end with boy and dog frozen to death on the tundra, did you? Not even Ellison and Jones opted for such a devastating denouement, though Jones added a particularly cruel closing touch to his version of the story. A final shot suggests that what Keda and Alpha have achieved represents a major change in human, as well as animal, life on earth.

The real heroes of “Alpha” are the craftsmen behind the screen—production designer John Willett, cinematographer Martin Gschlacht and the effects crew in particular. One must also, however, credit Albert Hughes, directing his first movie without his brother Allen as a team. He secures solid performances from his stars—gangly Smit-McPhee, who handles the physical demands well while eliciting sympathy for the desperate Keda’s plight, and (with the help of a talented trainer, one assumes) the expressive Chuck. The rest of the cast is adequate, with Jóhannesson in particular making a strong impression, though a few hints about several tribesmen (some suggesting a possible contest for leadership) go nowhere. The score by Joseph S. DeBeasi and Michael Stearns adds to the grandiosity of the images.

“Alpha” might not become the alpha dog among other warmer, fuzzier canine movies, but it’s certainly distinctive, particularly in visual terms.

By the way, if after a few months you rent this movie for home viewing (though it really deserves to be seen, if at all, on the biggest possible screen), be sure not to confuse it with 2007’s “Alpha Dog,” or you and your family will be very surprised.