'Smaug' is another slog through Middle-earth

• USA TODAY Review%3A ** %28out of four%29
• Stars%3A Martin Freeman%2C Ian McKellan%2C Richard Armitage%2C Orlando Bloom%2C Evangeline Lilly%2C Lee Pace%2C Aidan Turner
• Rated PG-13%3B runtime%3A 2 hours%2C 41 minutes%3B opens Thursday in select cities and nationwide on Friday

Smaug is not so much desolate as he is a one-dragon demolition derby in the latest Hobbit entry.

Despite his billing, the titular Smaug doesn't show up until 2 hours into The Hobbit: Desolation of Smaug (** out of four; rated PG-13; opening Thursday night in select cities and Friday nationwide). With his slyly toothy grin, he looks impressive enough, but his scenes are only mildly diverting, growing repetitive and dragging on.

The fantasy tale has its liveliest moments earlier. At least this installment doesn't begin, as the first did, with drunken revelry, goofy singing and dish-washing. But, like its predecessor, it features way too much trudging through forests.

Despite possessing the commanding voice of Benedict Cumberbatch, the fire-breathing beast's clashes with Bilbo Baggins (Martin Freeman) are largely anticlimactic.

Director Peter Jackson is an undeniable master of special effects. In 3-D, whizzing arrows and hovering insects make a playful presence. But not much happens in this second part of Jackson's adaptation of J.R.R. Tolkien's 1937 book.

The film's highlight is a thrilling action sequence in which a dozen dwarfs, riding inside wooden barrels, careen down a rapidly rushing river. A few elves on the sidelines fling arrows. But it's the vicious pouncing orcs that the dwarfs are desperately dodging in this edge-of-your-seat segment. Nothing else in the story comes close to packing in this much fun and excitement.

It's a continuation of the odyssey begun in last year's The Hobbit: An Unexpected Journey with the furry-footed Bilbo assisting 13 dwarfs in reclaiming their ancestral homeland from the fearsome dragon who now rules it. Led by Thorin Oakenshield (Richard Armitage), the heir to the dwarf throne, these voyagers tangle with giant arachnids, haughty elves and, of course, said dragon. The greedy behemoth is hoarding massive treasure, including the Arkenstone, a jewel sacred to the dwarfs.

Speaking of significant jewelry, Bilbo has his precious ring along on the trek, rendering him conveniently invisible whenever he slips it on. But he seems to do a lot of inexplicable holding and gazing at the ring, when he should be rapidly sliding it on his finger and moving on with things.

A couple of new characters are introduced in Rivendell, the stunningly beautiful elven realm. Teenage girls should welcome the return of handsome Legolas (Orlando Bloom) who is subtly romancing Tauriel (Evangeline Lilly), an auburn-haired elf created by Jackson, not Tolkien. Legolas' xenophobic father, King Thranduil (Lee Pace) disapproves of his royal son consorting with an independent woodland elf warrior like Tauriel. Meanwhile, Tauriel is drawn to the best-looking of the dwarfs, Kili (Aidan Turner). The story needed more female characters but Tauriel's presence feels tacked-on.

Once the ragtag band reaches Smaug, it becomes an all-too-familiar tale of a gargantuan beast whose clutches the good guys must avoid.

The story's power struggles seem muted in this adaptation, with greater focus on production design than character development.

The wizardly Gandalf (Ian McKellen) metes out orders and then takes off with little explanation. An expert delegator, he's an epic fail when it comes to reliability and morale-building. His shrugging assessment of one potential co-conspirator is: "He'll either help us or he'll kill us."

It's hard to care about the fate of any of these characters when the dwarfs seem so interchangeably played for comic effect. Sure, it's a more whimsical tale than the ambitious, masterly Lord of the Rings trilogy. But when it's not stalled on silly, it falls into slog territory.