"Quite a few people are saying that," said Jackson, 52, sipping tea between photos shoots at a Beverly Hills hotel. "We are consciously trying to deepen the characterisations and conflicts without straying too far from Tolkien." Peter Jackson, left, during the filming of The Hobbit: The Desolation of Smaug. Credit:AP Yet last year, when The Hobbit: An Unexpected Journey opened, many fans struggled to embrace the film, even as it raked in $US1 billion worldwide at the box office. Detractors seemed saddened that the soaring sense of adventure and heart that had defined the Rings films had gone missing, replaced by flatulent trolls, moments of slapstick humour and sluggish pacing. Only the sequence featuring the creature Gollum was universally praised as matching Jackson's earlier, Oscar-winning achievements. By contrast, Smaug is brimming with action, including a show-stopping fight sequence filmed along New Zealand's Pelorus River. In its grand scope and serious tone, it feels far more akin to Jackson's original trilogy than its immediate predecessor.

The story primarily centres on the middle portion of Tolkien's landmark 1937 youth novel, but Jackson and his writing partners Fran Walsh and Philippa Boyens have expanded the narrative to include new characters and moments referenced in the appendixes of The Lord of the Rings. Peter Jackson and his daughter Katie at the Los Angeles premiere of Smaug on December 2, 2013. Credit:AFP "That was one of the decisions we made at the very beginning," Jackson said. "Do we take a children's book, a very simplistic children's book, and faithfully adapt it? Or do we make a film that will live alongside the other three movies that we made? We are the same storytellers, Philippa, Fran and I, we're the same people working on it. We're trying to be faithful to the style and the tone." That Jackson returned to another Tolkien film at all was somewhat unexpected. After the Rings trilogy, he directed a remake of King Kong and The Lovely Bones, an adaptation of Alice Sebold's bestseller, though neither caught fire in the same way his Middle-earth movies had. He'd been set to produce The Hobbit as a two-parter helmed by Guillermo del Toro, but once Del Toro stepped down in 2010, it wasn't long before Jackson assumed the reins, expanding the project to three movies. (The third, The Hobbit: There and Back Again, is set for release in December 2014.) In this second portion of the saga, Martin Freeman's good-natured Hobbit, Bilbo Baggins, continues on his quest to help the dwarf king Thorin Oakenshield (Richard Armitage) and company reclaim the treasure of their lost homeland Erebor, which has been usurped by the evil dragon Smaug (Benedict Cumberbatch). Ian McKellen's wizard Gandalf has more of a solo role to play, ferreting out a great, ancient evil that is settling over the land.

Bilbo and Thorin's travels take them to the forest of Mirkwood, where they encounter not only giant, woodland spiders but also a race of Sylvan elves that includes Orlando Bloom's regal Legolas (a featured member of the Rings ensemble) and Evangeline Lilly's warrior Tauriel. She is the first character wholly invented for a Tolkien film by Jackson, Walsh and Boyens (Del Toro also is credited as a screenwriter on Smaug). We are consciously trying to deepen the characterisations and conflicts without straying too far from Tolkien. "For some reason that I don't quite understand, a lot of women love these stories more than other types of fantasy," Jackson said. "We just felt it was a bit male-heavy and we could do something about it." There are other new players, including Luke Evans' human Bard the Bowman, who resides in the enclave of Lake-town, which sits in the shadow of the Lonely Mountain near the deserted area known as the Desolation of Smaug. Narratively, Jackson said he felt greater freedom with this instalment than with Unexpected Journey or the upcoming There and Back Again. He neither had to establish the story and introduce the characters nor deliver "an exciting climax" for the trilogy.

But there was dragon anxiety. He acknowledged that he felt some apprehension over finally bringing Tolkien's great red-golden beast to the screen. "You keep hearing all this expectation," Jackson said. "'I want to see Smaug, I want to see Smaug.' I hadn't seen Smaug up until a few months ago, really, not in his current form! "Those things," he added with a laugh, "are a bit of a pressure." Jackson said that for the scenes with the serpent – and the rest of the film as well – he, Walsh and Boyens constantly revised the script, trying to refine the story even as shooting was underway. Jackson went so far as to bring some of the actors back to his Wellington headquarters for 12 weeks last summer to film additional sequences for the final two movies, including the flashback scene between McKellen and Armitage that opens The Desolation of Smaug. "We literally don't stop writing," Jackson said. "Just because you've cast the film, just because you've started shooting, just because you've got actors asking, 'What exactly are we shooting tomorrow?' – none of that is a reason not to write, not to try to improve."

Evans (Immortals, Fast & Furious 6) said he flew to New Zealand for his Bard the Bowman part without having read a script. "I had to trust the word of Philippa Boyens and Peter Jackson that I hadn't just signed away 18 months of my life for a little flash-in-the-pan role," the Welsh actor said. "As soon as I got off the plane, the script was there. I got to read it and wiped my brow at the end. I was very pleased and relieved." Maybe it's the fervour over the dragon, or improvements made by Jackson's incessant revising, or some other alchemical filmmaking charge, but movie critics have expressed their own pleasure with The Desolation of Smaug in early reviews. At this point, the film is poised to become Jackson's most acclaimed offering since 2003's Return of the King, which claimed 11 Oscars. It bodes well for the film showing in both the hyper-real 48 frames per second rate that Jackson has been advocating and in the conventional 24 frames per second rate. Early tracking suggests that the movie could open to $US75 million, though the take could go as high as $US90 million. No matter how the movie ultimately fares, Jackson said he's pleased that his films have helped bring Tolkien's magic to new generations of readers.

"The great thing about the movies is that they have increased the book sales enormously," Jackson said. "Huge numbers of people are reading Tolkien now, and I'm happy to claim some credit for that. "Any of the liberties that we take in adapting, any of the changes we make, any of the things that might have upset Professor Tolkien ... it's not all take. We do give something back." Loading Los Angeles Times