So you’re driving down the freeway late at night, and out of nowhere this strange electronic anomaly appears right in the center lane.

And then, before you can say Firefly, there’s three naked people standing in the road while cars all around you swerve off onto the shoulders. Naturally, your kid starts flashing cell phone pics of the unclad trio from the back seat so the evening news will have some footage. And before you can say Serenity, they’re gone. You might be inclined to let someone else drive a while.

And that wasn’t even the most surreal moment of Terminator: The Sarah Connor Chronicles, which was previewed at Yahoo TV the last 24 hours.

No, that distinction goes to Summer Glau, as Cameron the good terminator, moments after she sent Cromartie, the evil terminator, flying from the grill of a pick-up truck.

“Come with me if you want to live,” she tells John Connor (Thomas Dekker), sounding not a bit like Schwarzenegger yet channeling the continuity from Terminator 2: Judgment Day, from whence Fox’s new sci-fi series picks up.

The online sneak preview had me glued to my computer screen, which says a lot since I don’t particularly enjoy watching shows this way.

You know the back story. SkyNet is destroyed, and the future is unwritten, or so Sarah Connor thinks. She’s still on the run from the law, trying desperately to keep her son John, future leader of the human resistance, safe. But no one is ever truly safe, goes the mantra she hammers home with John.

Sure enough a substitute teacher pulls a semi-automatic out of his thigh (literally!), blows away the hot new girl in school and dismisses class in unceremonious fashion. The machines are back. Someone went ahead and built SkyNet anyway. John decides he can’t run anymore and convinces Sarah to fight back.

And there’s your open-ended premise for a series that launches in the present day, some three-plus years before SkyNet becomes self-aware and declares war on humanity.

The positively mesmerizing Summer Glau of Serenity and Firefly fame says more with her eyes than with her short, calm, near emotionless lines, she might be the most convincing terminator since Arnold in the original. (He got a little too “human” for my taste in T2.) She’s a new model, different from the others. She eats corn chips. You just know John’s wondering what else she does like a real girl. (The line of the episode goes to Sarah, speaking to Cameron who is pulling bullets from her topless torso: “You might want to put those back in the holster.”)

Dekker, for his part, is a serviceable John, similar in appearance to Nick Stahl, who played the role in T3: Rise of the Machines (which doesn’t figure into the new show’s chronology or mythology). Both actors play to the hilt the angle of reluctant hero, too soft to lead an army. It’s a little grating, to be honest.

Lena Heady, meanwhile, does Linda Hamilton proud. She’s every bit the secretary-turned-soldier-of-fortune Hamilton portrayed in T2. But unlike Hamilton, the portrayal never becomes comical, probably because the part is written to reflect the genuine anguish of a mother who doesn’t need the fate of humanity as motivation to protect her son. By the way, Heady is yet another accent-suppressing Brit actor on American prime time, joining Jamie Bamber (Battlestar Galactica) and Hugh Laurie (House) and following on the heels of the disappointing Michelle Ryan (Bionic Woman).This pilot had quick-paced action, plenty of violence and yet a thoughtfulness about the quandary the characters face. They and the story being told confront the same dilemma: everyone knows how things end. The machines rise up, Judgment Day comes and John Connor is mankind’s hope.

The fun will lie in getting from A to B.

Make no mistake, though. This isn’t John Connor’s story, and it isn’t about the Terminator. As the title implies, these are the chronicles of Sarah Connor. It’s all from her perspective, and I have to expect it’ll all be about her in the end.

I’m wary about the time travel. I’ve said it before, it’s the most intriguing and potentially horrendous sci-fi device. After all, if the machines could plant futuristic weapons and time machines throughout the world and throughout recent history, there is no conflict that can withstand the scrutiny of a simple question: Why not go back in time and change things? The more sparingly it comes into play, the better.

FBI agent James Ellison, played by Richard T. Jones, is always on the Connors’ trail. He seems like he’ll provide a reality-check to the space-time continuum/global annihilation vibe and give the audience a character whose perspective they can share.

If the creators can sustain the intensity of the pilot, avoid gimmicky sci-fi trickery like finding time machines laying about when things get tight and somehow keep Glau from stealing too many scenes like she did a bit of in the premiere (a la Katee Sackhoff in Bionic Woman) , this show will be a staple on my DVR playlist for a long time to come.