That thing they say about men with big feet, it clearly doesn’t apply to hobbits — at least, it doesn’t matter. With all those long quests, endless days cloaked in physical and spiritual enfeeblement, you’d think one of them would opt for a night’s distraction, a well-earned roll in the hay. But no. The morning dawns and the quest resumes. JRR Tolkien’s characters are cut from sterner cloth than the people that populate the lusty adventures we know and love, like the Robin Hood tales or the Arthurian legends. Even their constitutions appear other-worldly — all that trekking over mountains and into the bowels of Middle Earth, and no one sheds a kilo.

Peter Jackson’s toughest challenge, with the three Lord of the Rings movies earlier and with The Hobbit trilogy now, has been to humanise these impossibly exalted archetypes, draw them closer to our realm of experience, so that we are invested not just in what they do but who they are.

And as with the earlier movies, Jackson does this beautifully in The Hobbit: An Unexpected Journey. Take, for instance, Gandalf (Ian McKellen). He’s fleshed out as a pointy-hatted purveyor of orotund wisdom and an eccentric old man who polishes the stem of his pipe with his flowing beard — but more crucially, we sense a canny manipulator, the template for the wise and eccentric Professor Dumbledore, him of the equally formidable beard.

After an amusing sequence (which, like everything else in the film, goes on a little too long) where the hole-in-the-ground home of the hobbit Bilbo Baggins (Martin Freeman) is invaded by a horde of dwarves, it is decided that Bilbo will accompany his uninvited guests on a quest to reclaim their lost gold from the lair of the dragon Smaug. The dwarves’ leader Thorin (Richard Armitage), unconvinced about this arrangement, whispers to Gandalf that he won’t be responsible for the hobbit’s life — and Gandalf simply nods, no more troubled about Bilbo than a chess player about to sacrifice a pawn.

How easy it must have been, for Jackson and his writers, to reduce Gandalf the Grey to Gandalf the Black-and-White, an unvaryingly crowd-pleasing dispenser of magic. But if we are to care about characters over decades — the first Lord of the Rings film was released in 2001 — then this is how they should reveal themselves, slowly, in layers.

A different kind of slowness, however, hampers The Hobbit, which begins briskly enough, with scenes featuring the older Bilbo (Ian Holm) and Frodo (Elijah Wood) that refer to a future where Lobelia Sackville-Baggins will be suspected of stealing Bilbo’s silver spoons while also reminding us about the past. Like the first Lord of the Rings film, The Hobbit, early on, contains a scene-setting flashback of a great war, but unlike that film, we don’t hit the ground running. Part of the problem is the significance of the quest. An evil-enabling ring portends the end of the world; a treasure in a distant dragon’s lair merely points to adventure.

Added to this lack of immediate urgency is Jackson’s decision — no doubt with an eye on the box office (why make one money-spinner when you can make three?) — to prostrate himself before Tolkien’s prose. The Hobbit is not so much an adaptation as a fossilisation of every page, every paragraph, every comma and period, and at times, we wonder if we’re watching a movie or a mini-series. Some of the scenes go on forever.

With all this dawdling, our attention wanders from the story and the characters, and we begin to notice how similar these extensively post-produced movies have come to look.

This isn’t to demand the constant creation of unseen, unimaginable worlds and their inhabitants — merely to suggest that, unless coloured with distinctive personality, everything is interchangeable. This is also another way of saying that every fantasy-film franchise needs its Gollum.

The Hobbit is stuffed with orcs and trolls and stone giants and giant eagles, and it thunders along with manically detailed action set pieces — one across a bridge, with malignant goblins multiplying like cancer cells, is particularly impressive — but it’s upon Gollum’s entry that this fantasy turns truly fantastic. The remarkable Andy Serkis, as always, plays the part, and the stretch where Gollum and Bilbo dance delicately around each other, armed only with riddles, is the film’s most thrilling battle. With the gaze telescoped from the general to the specific, something, finally, seems to be at stake.

Martin Freeman is excellent at conveying flustered bewilderment, which Gollum counters with schizophrenic scheming — not for an instant do we doubt that they really exist, that this really happened.

Of The Hobbit this much can be said: it gets better as it goes along, and it lays a solid foundation for the future films. But this much should be said: it’s time to institute an Academy Award for Best Supporting Creature.

The Hobbit: An Unexpected Journey

Genre: Fantasy-adventure

Director: Peter Jackson

Cast: Martin Freeman, Ian McKellen, Richard Armitage.

Storyline: A hobbit and a horde of dwarves set out to retrieve treasure from a dragon.

Bottomline: Slow going at first, but still a solid foundation for the future films.