Improving on the "performance capture" technique he employed so skillfully in "The Polar Express," director Robert Zemeckis has fashioned a rousing version of the oldest poem in Anglo-Saxon literature, one famously championed by J.R.R. Tolkien in a 1936 essay.

The new "Beowulf" (Paramount) is a generally impressive animated reworking of the Scandinavian legend, to be shown in vivid 3-D as well as conventional two-dimensional versions.

The narrative begins with the titular warrior's (Ray Winstone) arrival in the Denmark of 507 during which he boasts he will rid the beleaguered King Hrothgar (Anthony Hopkins) and Queen Wealthow (Robin Wright Penn) of the giant, grotesque demon Grendel (Crispin Glover) who makes periodic deadly encroachments into the king's hall.

It's a court of great debauchery, as we glean from the king's exhortation to "merriment, joy and fornication." Wealthow is unhappy with the licentiousness about her, and looks with favor upon the seemingly upstanding Beowulf.

Beowulf is fully confident he can vanquish Grendel, despite courtier Unferth's (John Malkovich) denouncement of Beowulf's prior deeds -- such as a swimming race at sea -- as fraudulent exaggeration, a charge Beowulf quickly refutes with details of how he triumphed over monstrous sea creatures, though the dramatized flashback shows his account is not entirely accurate, presaging later events.

When Grendel -- a tortured, pathetic creature -- makes his terrifying appearance that night Beowulf is more than up to the challenge, eschewing sword, shield and clothes. In fact, he makes the skimpily-clothed Spartans of "300" look positively bundled up!

Grendel dies a piteous death, but his wicked mother (Angelina Jolie) -- a naked, gold-plated seductress with a tail -- proves an even greater challenge. Here's where Neil Gaiman and Roger Avery's script veers most from its source. Rather than killing her, Beowulf succumbs to her seductive wiles, their implied romantic encounter generating sorry ramifications later on.

Zemeckis has clearly taken some dramatic license with the venerable but sketchy original narrative, but the intelligent screenplay remains faithful to the essentials, including a nod to Christian and pagan elements. There are various Christian symbols throughout, even if Beowulf decries the passing of true heroes for "weepy" Christian martyrs. Still, whether our antihero likes it or not, the film makes clear that the pagan times are passing. Beowulf emerges a flawed, complex hero -- undone by his lust for power -- his sins most assuredly coming back to haunt him.

Overall, the script overall has an admirable gravitas, and a surprisingly sophisticated, elegiac tone for this genre. The acting is uniformly good, including Brendan Gleeson as Beowulf's hero-worshipping sidekick and Alison Lohman as Beowulf's mistress.

The performance-capture technique allows several of the performers to look much like their real-life selves, though it also gives the nudity and violence a realism far beyond standard animation. Several of the action sequences, including the climactic battle with a flying dragon -- with an aged Beowulf hanging on for dear life, are brilliantly and excitingly executed.

The film contains nearly full male and female nudity, sexual references and innuendo, period bawdiness, adultery, implied nonmarital encounters, intense violence with gore and a suicide. It is possibly acceptable for older teens. The USCCB Office for Film & Broadcasting classification is A-III -- adults. The Motion Picture Association of America rating is PG-13 -- parents strongly cautioned. Some material may be inappropriate for children under 13.

Movies have been evaluated by the U.S. Conference of Catholic Bishop's Office for Film and Broadcasting according to artistic merit and moral suitability. The reviews include the USCCB rating, the Motion Picture Association of America rating, and a brief synopsis of the movie.

The classifications are as follows:

• A-I -- general patronage;
• A-II -- adults and adolescents;
• A-III -- adults;
• A-IV**
• L -- limited adult audience, films whose problematic content many adults would find troubling. L replaces the previous classification, A-IV.
• O -- morally offensive.