Ever since wizard Gandalf the Grey (Ian McKellen), hobbit Bilbo Baggins (Martin Freeman), and their thirteen dwarf companions led by Thorin Oakenshield (Richard Armitage) were flown to safety on the backs of giant eagles at the end of 2012's 169-minute "The Hobbit: An Unexpected Journey," director Peter Jackson's three-part adaptation of J.R.R. Tolkien's comparatively brief 300-page novel has all but entirely collapsed with a plot discrepancy that cannot be overlooked. Had Jackson and co-writers Fran Walsh, Philippa Boyens and Guillermo Del Toro tackled Tolkien's source material in a single, three-hour epic, perhaps such narrative stumbles wouldn't appear so egregious. When turgidly stretched out to almost nine hours, however, the realization that said eagles could have easily been called upon at the start of these characters' travels to transport them within moments to their destination in the Lonely Mountains renders the first two films all but pointless. As blatantly padded as "The Hobbit: An Unexpected Journey" was, it is no match for the frustratingly inert, drawn-out, snail-like pacing which middle chapter "The Hobbit: The Desolation of Smaug" is guilty. Were it not for its typically first-class production values, this lugubrious trilogy could easily be confused as the cinematic equivalent of derivative, threadbare fan-fiction from someone who's seen Jackson's own "The Lord of the Rings" series too many times.

Much like 2002's "The Lord of the Rings: The Two Towers"—only doubly shameless—"The Hobbit: The Desolation of Smaug" has no beginning or ending, picking up as the story is in midstream and entirely lacking a three-act structure. While this was sort of understandable with "The Two Towers," "The Hobbit" is a different animal altogether. Jackson can toss in as many appendices separate from the central source material as he likes, but it is not going to change the concrete fact that this project had no business being turned into three separate movies. The premise is simple—and, let's just say it, a less complicated, less interesting variation on "The Lord of the Rings"—but one can imagine how it might have been turned into a single truly great, tautly conceived, propulsively realized fantasy adventure. By cutting it into thirds and overstuffing it with trivial-to-the-point-of-pompous filler, Peter Jackson has dug his own creative grave while taking advantage of his audience. In every way outside of its still-dazzling technical feats, "The Hobbit" is shaping up to be a languid, inferior, very nearly embarrassing stain on the legacy and achievement of the collective "The Lord of the Rings" trinity.

In "An Unexpected Journey," Gandalf, Thorin & Co. traveled to the peaceful Shire to seek the aid of one Bilbo Baggins. Hobbits are known for their sneaky burgling know-how, and Bilbo was christened their best bet to accompany them on a perilous journey to the Lonely Mountains, located in Erebor, to defeat the fire-breathing dragon Smaug and retrieve the treasures stolen from them. In "The Desolation of Smaug," they continue their hiking-heavy expedition, fighting off Orcs, escaping from captivity from the wood-elf community, and riding wine barrels down the river rapids. With the secret door at the foot of the mountain only opening on the last day of autumn, they have a very narrow window in which to make it there. Getting past Smaug and retrieving the magical Arkenstone, swiped from Thorin's family when his kingdom was overtaken, will be no easy task.

"The Hobbit: The Desolation of Smaug" feels like a chore rather than a source of entertainment and/or enlightenment. Beyond the less engaging lead protagonist—try as he might, Martin Freeman (2013's "The World's End") is no match for Elijah Wood's Frodo or, for that matter, the elder version of Bilbo played by Ian Holm—the film's forward movement acquires the sensation of mucking one's way through a swamp: it's arduous, monotonously slow-going, and not particularly fun. The plot has no real complexity to it, which calls all the more attention to its lack of momentum. Thirty minutes go by at a time with nothing notable happening, becoming a test in just how long the wheels can be spun while remaining in the same place. Characters are either functional, unnecessary, or astoundingly unformed. For two pictures now, twelve of the thirteen central dwarves are still barely more than faces in a crowd. Some ensemble additions, such as elven warrior Tauriel (Evangeline Lilly), are newly invented and did not appear in the book. The usually bland Orlando Bloom (2007's "Pirates of the Caribbean: At World's End") reprises his role as Legolas—and may have even gained a hint of a personality in the ten-year interim since 2003's "The Lord of the Rings: The Return of the King"—but, as another add-on that wasn't in the novel, his participation feels like a flimsy excuse to shoehorn familiar faces into the proceedings.

J.R.R. Tolkien's "The Hobbit" was published in 1937, seventeen years before his "The Lord of the Rings" opus. At the time, there was likely a hearty helping of suspense in seeing Bilbo through to the end. Would he and Gandalf survive their quest? Would the riches lorded over by Smaug fall to their rightful owners? Since the film versions of "The Lord of the Rings" movies came out a decade ago—and "An Unexpected Journey" began with a wraparound sequence as the elderly Bilbo weaves the tale to Frodo—there is no question anymore what is going to occur. Bilbo and Gandalf will, indeed, survive to see many more days and years, and all will more or less work out. The prequel aspect of "The Hobbit" is yet another fatal error in this cinematic undertaking's conception. Where is the stirring danger and palpable threat? Where is the fear? And why does Jackson rely so heavily on the old contrived standby of characters constantly being saved from certain doom as an ally rushes in at the last second to save the day? This would get tedious after a while if the whole picture weren't already so insipid.

By the time Bilbo has found his way into the cavernous mountain lair and accidentally awakened the malevolently imposing Smaug, "The Hobbit: The Desolation of Smaug" has already worn out its welcome and expectations have been deflated like a withered, ten-day-old balloon. Par for the course, director Peter Jackson and editor Jabez Olssen (2009's "The Lovely Bones") extend this confrontation by twice as long as it needs to be, then conclude on a note that would have worked so much better as the thunderous start to a climactic third-act. Instead, it abruptly cuts to the end credits—a final unsatisfying slap in the face that diminishes the material and only confirms that "The Hobbit" should have been a big one-and-done film. Smaug, performed via motion capture by Benedict Cumberbatch (2013's "12 Years a Slave"), is an astonishingly designed and photorealistically rendered creature, bursting with all the fiery brimstone and portent one could only dream for this daunting villain. He's awesome, and the rest of the visual effects artistry and lavish costumes and art direction are never less than impressive. Where "The Hobbit: The Desolation of Smaug" gasps its last breath of life is on the screenwriting level and all of the misfires that have gone into this strained series' misbegotten construction. It took five movies for Jackson to make a truly bad one about Middle Earth. He should have stopped two films ago while he was still ahead.