Ever since Arnold Schwarzenegger came back from the future to kill Linda Hamilton so she couldn’t give birth to Edward Furlong, the “Terminator” series has been on a time-illogical crash course with itself. Eventually the future has to catch up with the past. Or something like that.

But it seems unlikely that audiences will be caring much about the niceties of relativity when “Terminator Salvation” offers so many outsize distractions: towering mechanical assassins; writhing, giant-sub-sandwich-size chrome centipedes; humans engaged in an epic battle for the planet itself — and a movie that mixes summer blockbuster hysterics with moody, visual grit.
Ex-music-video maker and “Charlie’s Angels” director McG, ignoring the constraints of the time-space continuum and essential insanity of the franchise, approaches “Terminator Salvation” with near-Talmudic gravity. The result is a movie that takes itself far more seriously than the “Hasta la vista, baby” tone of previous installments.
But he doesn’t skimp on the scary stuff. Picking up the apocalyptic cue from “T3” — in which the leader-to-be of the human rebellion, John Connor, is still waiting for all hell to break loose — McG drops us in 2018, with the machines of the malevolent/corporate Skynet well into their campaign against humankind. Connor (Christian Bale) is at this point an insubordinate lieutenant to Gen. Ashdown (Michael Ironside), but has been prophesied to be the savior of mankind. Hence all those Skynet-commissioned trips by cyborgs trying to kill him in the past. And the urgency of keeping him alive for the future.
We moviegoing, 2009-model humanoids exist in a cinema world where almost anything seems possible on-screen, and thus very little is still capable of nailing us to our seats. But McG manages to create palpable fright, mostly through his use of time: When rebel woman Jane Alexander is suddenly plucked out of our field of vision and through the roof of a shanty, it happens with an abruptness that tells us we better keep our eyes peeled. Anything might happen (like the skyscraper-size robot that just appropriated Jane). When it does, we don’t have the luxury of slo-mo.
The wild card in all this “T”-ness is Marcus (Sam Worthington), a death row inmate-turned-cyborg. The opening scene of the film finds Marcus being visited in his cell by a ghastly looking, cancer-stricken Dr. Serena Kogan (Helena Bonham Carter), who wants Marcus to okay the use of his corpse for cyborgification — which he does, in exchange for a kiss (“So that’s what death tastes like,” he murmurs, as she scurries off). Marcus reawakens, post-lethal injection, during the war in a howling allegory of birth. (Remember John Goodman coming out of the earth in “Raising Arizona”?) He is immediately a man without a country. “You think you’re human,” the hostile Connor says to him, and indeed he does. More important, so do we: Marcus the machine is a far more interesting character than Connor, whom Bale portrays with a single-minded furiousness that is less engaging than Marcus and his conflicts.
Whatever he did to get on death row haunts Marcus in his second life, as does the vague memory that he used to be human. What will likely haunt Bale is the thought that another supporting player has stolen his movie (see: Heath Ledger, “The Dark Knight”).
McG employs a scheme bleached of color and informed by ash and grime. The world he presents to us is all plausibly scorched and hostile — Los Angeles, post-Skynet-attack, is particularly affecting. It’s there that Marcus finds the L.A. contingent of the rebellion — both of them: the teenage Kyle Reese (Anton Yelchin), who is supposed to grow up to be John Connor’s father (see what we mean about that time-warp collision course?) and Star (Jadagrace), a mute, charming rebel grrrl with a great sense of timing.
The dark mood of “Terminator Salvation,” which is relieved occasionally by the script going completely out to lunch, might have come off as pretentious but instead seems tonally organic and relatively believable. The action is startling and visceral, and adds to a movie that’s as believable as it can be when its subjects are besieged humanity, occupational forces, rebel insurgencies, torture, lawlessness and warfare by remote control. Anything resembling real life in “T4” is no doubt a total coincidence.