Clash of the Titans” is a cheesy-as-hell remake of a 1981 film that treats Greek mythology as fact, revels in low-grade graphics and stars Trey MacDougal from “Sex and the City.” In a nutshell: The revamping involves minor storyline tweaking, dramatically improved effects and Sam Worthington — otherwise known as this year’s Matt Damon, if Matt Damon didn’t know how to act.

To make things worse, the first 15 minutes of the film are comprised of foreshadow overkill. Without a booming intro or scrolling text to set the scene, we find ourselves wondering why these stupid 3-D glasses are resting on our noses at all.

Fortunately, the next hour provides a significant degree of relief. Who knows what director Louis Leterrier (“The Incredible Hulk”) started smoking, but the story of Perseus — the unwilling demigod who must prevent his uncle Hades from destroying the human race and conquering the world — is surprisingly captivating. It sounds like the plot to a half-baked children’s movie, but “Titans” is actually quite enthralling, and not in the horrific train-wreck way you might expect.

How it remains appealing until the end credits is the great mystery. After all, it’s a “Lord of the Rings” quest set in the location of “Troy,” with a villain who looks like Voldemort’s twin and Liam Neeson as Zeus. But for some reason, all those contrary elements come together to make a piecemeal film that reflects the better qualities in its inspirations.

Look out for one hilarious “Avatar” parallel after another, as Perseus rides Pegasus in a scene that raises the question of why Worthington is so good at mounting winged fictional creatures. But there’s just enough myth in “Titans” to create its own unique story with a touch of campy action, which is all we need to sit back and enjoy.

That’s not to say the film is without fault. Sticklers for Greek mythology will find discrepancies in the myths; for example, the character Io claims a god made her immortal as a punishment, when she should have turned into a cow. However, it’s not hard to see why Gemma Arterton would have had problems emoting from the CGI form of a talking quadruped, so that one can be overlooked for the sake of the story.

Of course, the major blockbuster contains more than its share of cheese, as lines like “Release the Kraken!” and “Tame your storm!” are delivered in the utmost seriousness — making for the best mindless fun since the crotch shot in “LOTR.”

The film’s only serious flaw is that it’s not worthy of 3-D. There are no overly exciting graphics (nor any obnoxious ones, for that matter). But if you’ve got itch for ancient Greece, this one’s pure gold; just take my advice and save yourself the $3 extra — who wants to be a four-eyed loser for no good reason?