Writer-director DeBlois strikes just the right balance between knockabout comedy, action and heart-tweaking family drama.
It helps, too, that there is such lively voice-work from the likes of Gerard Butler (playing Stoick, Viking Chief of the Hairy Hooligans, with an exaggerated Scottish burr) and Cate Blanchett (as the long lost wife, mom and dragon lover Valka.)
The hero, Hiccup (Jay Baruchel), with his one missing leg, is an engagingly mischievous figure who dotes on his pet dragon Toothless (and Toothless in turn slobbers all over him, like a pet labrador.)
With his long black braids, growling voice and permanent scowl, Drago Bludvist (Djimon Hounsou) makes a suitably ferocious villain. The 3D is put to good effect as dragon patrols fly through the icy skies or as Hiccup stumbles into a magical, Edenic kingdom where dragons big and small roam free.
None of the ideas here are especially original. For fiery beasts, the dragons are sometimes just a little bit too much on the cuddly gonk side.
Only in the final reel battle sequences are we given a sense of just how lethally these winged creatures can behave.
The filmmakers borrow freely from Avatar, Sword In The Stone and even Brave but they bring enough vigour and imagination to their storytelling to get away with it.