NBC is touting Robert Halmi Sr.'s three-hour "Hercules" movie as "the definitive retelling" of the mythological muscleman's life. Well, not quite.

Certainly it hews closer to the original myths than "Hercules: The Legendary Journeys," the late-1990s syndicated hit that transplanted the hero from ancient Greece to some vaguely medieval time and represented him as a tanned and wiry surfer type (Malibu Herc?) who dressed as though he were fronting Aerosmith or Def Leppard.

But if you want to see how much Halmi and screenwriter Charles Edward Pogue have modified or left out completely, grab a copy of "Bulfinch's Mythology" or look up "Herakles" on the Web at www .mythome.org/greek.html. As labyrinthine as the movie's plot may seem, it's as straightforward as an episode of "JAG" compared to the infinitely twisted yarns of yore.

Halmi's is sort of a secular-humanist Hercules. Or maybe Unitarian. Zeus, Hera and other Greek gods are prayed to and yelled at but never actually depicted on-screen, and even Hercules' son-of-a-god lineage is questioned. Near the end, he makes a big declaration from a sea cliff's edge about respecting and worshiping all creation but having had his fill of fickle creators.

Half of the famous 12 labors of Hercules are omitted. In the case of his cleaning the Augean stables, where 3,000 oxen had done their business for 30 years, it's probably just as well. But it would have been fun to see him temporarily relieve Atlas of his burden - holding the heavens on his shoulders - in order to retrieve the golden apples of Hesperides.

Then again, maybe not. The movie's computer-animators have a difficult enough time bringing to life the lesser labors - slaying the Nemean lion, orwhacking

the multiheaded Hydra - without generating unintentional laughs.

The CGI creatures - centaurs, golden stags, bird-like harpies that fling off feathers like knives, the aforementioned Hydra - look halfway realistic in some shots, ridiculously artificial in others. But the effects are no more inconsistent than the actors, who often stumble over the obligatory semi-classical dialogue. Shouting lines at a thunderstorm is never easy, even if William Shakespeare provides them. And Pogue is no Bard.

Ex-007 Timothy Dalton ("License to Kill") and Elizabeth Perkins ("The Ring Two") occasionally wring some humanity from their roles as Hercules' loving stepfather, Amphitryon, and treacherous mother, Alcmene. As Deianeira, the nymph who eventually becomes Hercules' wife, Leelee Sobieski ("Joan of Arc"), comes across like a giant Tinkerbell who's spent too much time at a tanning parlor. Sean Astin ("Lord of the Rings") gets sidekick duty again, with much dopier dialogue. He's Linus, the lyre instructor young Hercules accidentally kills. In the myths, Linus stays dead. In the movie, he's revived and becomes Hercules' Sancho Panza.