When someone attempts to make over a successful television show, they almost always bungle it. “Bionic Woman.” “Knight Rider.” “Melrose Place.” They’re just a few notorious examples of recent reboots that quickly crashed and burned.

So when I heard CBS was going to remake “Hawaii Five-0” — a show that I maniacally cherished as a kid — I instantly experienced a case of cold sweats. “How many ways are they going to screw this one up?” I wondered.

But consider my mind happily blown. CBS has presented viewers with an exciting gift this fall. Their “Five-0” update not only doesn’t stink, it’s an action-packed, easy-on-the-eyes thrill ride that is slicker and sexier than the original series that aired from 1968 to ’80. It also contains a sense of humor that the stone-cold serious Jack Lord version lacked.

Stepping into Lord’s shoes as Detective Steve McGarrett, Oahu’s crime-fighting Big Kahuna, is Alex O’Loughlin, who after two strikes with CBS (“Moonlight”; “Three Rivers”) is getting his third — and probably final — swing.

And what a contrast he brings. Gone are the lacquered black pompadour, steely stare and granite jaw. Yes, O’Loughlin’s McGarrett is still a stoic man on a mission, but there’s an engaging hang-looseness to him. He prefers T-shirts to dark suits and isn’t shy about stripping them off to show off his rippled abs.

In tonight’s high-octane opener, McGarrett, is introduced as a decorated Naval intelligence officer who is out to crack a terrorist cell. But the murder of his estranged father brings him home to Hawaii, where the governor (Jean Smart) persuades him to stay and head up a new elite police task force. Explosions ensue. And gunfights.

The most dramatic — and best — change is McGarrett’s relationship with his sidekick Danny “Danno” Williams (Scott Caan). In the original, Danny, played by James MacArthur, was little more than a stage prop, doing what he was told, no questions asked.

But in “Five-0” 2.0, Danny has transformed from yes-man to wing man. He and McGarrett are more like equals — equals who engage in verbal (even physical) sparring matches. Their smack-talking banter helps to keep things playful, and Caan is a scene-stealing delight.

Rounding out the highly appealing cast are Daniel Dae Kim (“Lost”) and Grace Park (“Battlestar Galactica”). The latter brings a feminine touch that was virtually nonexistent in the testosterone-laced original. But better not cross her. This feisty surfer-chick packs a mean punch.

Even with all the updates, fans of the original will be pleased to see that some things haven’t changed. That iconic theme song is still intact. The Hawaiian scenery is still presented in all its blazingly beautiful glory. And we even get a heartwarming “Book ’em, Danno” line before the first hour expires.

It helps that executive producer Peter Lenkov was a big “Five-0” fan as a kid who watched the show religiously alongside his dad. With Lenkov at the helm, the franchise appears to be in good hands.

It also helps that the original wasn’t exactly “Masterpiece Theatre.” As much as some of us loved it, we can’t deny that it had its cheesy elements and was often stiff and stodgy. In its latter years, some episodes were just plain awful.

In other words, there was room for some contemporary improvement. And with that mission accomplished, “Hawaii Five-0” just might be one remake with staying power.