In the great mythology of movie monsters, every fiend contains an audience’s hidden fear. For the vampire, it’s the shame of infection. For the mummy, it’s the pain of memory.

And for the werewolf, it’s the mindlessness of hunger.

It might be, as in the old Lon Chaney stories, a thirst that hinted of addiction. It might be, as in more modern tales, an urge more akin to lust. But in all cases, the movies are about animal appetites, and how they destroy the human beasts who have them.

Unfortunately, the fiends of “Blood and Chocolate” seem merely … peckish.

Perhaps it’s the tween-friendly PG-13 rating, which means the story downplays physical details of all kinds. Perhaps it’s the rather obvious, arty touches its Euro cast and crew have embraced (like that title, a quote from Herman Hesse’s “Steppenwolf”). But there’s no real meat here – as the studio, which would not screen this in time for critics, certainly suspected.

Filmed in Eastern Europe, fabled home of gothic ghouls and low-budget filmmakers, “Blood and Chocolate” discards some of the old Hollywood myths to get back to older basics. These werewolves aren’t men who become wolfmen – noses painfully erupting into snouts, hands blunting themselves into paws – but humans who become wolves, loping along in human-hunting packs.

Every pack has a leader, of course, and this one’s is Olivier Martinez, once the young man who led Diane Lane astray in “Unfaithful,” now a werewolf king. He already has his new queen picked out, too – pretty American Agnes Bruckner. But she loves the mortal Hugh Dancy, and even a man who is pure in heart knows this is not going to end well.

The use of wolves instead of wolfmen is certainly a novel change, and Romania – with its Roman heritage and inescapable images of Romulus, Remus and their hairy mother – is an appropriate backdrop. Called upon to express existential despair, however, TV actress Bruckner looks merely sullen; as an impassioned artist, the lightweight Dancy seems as if a middling case of writers’ cramp would send him into intensive care.

The older actors fare better. Martinez has a little bit of command as the alpha male; the German actress Katja Riemann brings some real feeling to the part of one of his former conquests, now cast aside for a younger model but still waiting for her lover’s footsteps on the stairs.

But director Katja von Garnier, whose first American feature this is, doesn’t seem to have a clue. There is a long, terrible “falling-in-love” sequence of Bruckner and Dancy giggling and splashing about in fountains while pop songs play. There’s also far too much parkour, those urban French gymnastics that have gone from discovery to cliche in about 12 months and three movies.

As for the script, co-written by once-hot horror scribe Ehren Kruger – well, it has more howlers than the wolves. Some stumble toward profundity (“We are all lost souls, but at least we are lost together”). Others just stumble (“If you cared a thing about me, you would have left before we met!”)

If you’re a young fan who wants to see a not-too-scary scary movie dressed up with some they-just-don’t-understand-us young love, well, then “Blood and Chocolate” may just hit the spot. But if you want a little more from your hairy horrors, this is the sort of low-cal snack destined to leave you unsatisfied.

And maybe just a little hungry to rent “The Howling” again.

Rated: PG-13 for violence and mild sensuality. Rating: 2 stars. Running time: 98 minutes.