In 2008, writer-director Christopher Nolan transcended every possible notion about what a comic book adaptation could be and the depths to which it could delve with "The Dark Knight." To date, it still stands as the reigning achievement among superhero movies, deconstructing and revitalizing the genre in ways once thought unimaginable. Never one to take the easy road, Nolan has followed this up with another project of massive scope. Even better, it's based on an original idea, built from the bottom floor up within the mind of an auteur who could have just as easily developed a preexisting property—a graphic novel, a book, a video game—for the screen and cashed a quick, big check. A sci-fi heist picture occurring largely in the dreams of its characters, "Inception" has been meticulously formed and sculpted with notable ambition and storytelling proficiency. Nolan takes great pains in explaining the out-there complexities of his plot so that audiences won't be hopelessly lost, but in doing so he has ultimately neglected much of the film's vital human element while falling back on standard, formulaic, even laggard action set-pieces dressed up in artificially fancy threads. For a motion picture set within the boundless reaches of the subconscious, "Inception" is depressingly lacking in imagination.

In a world where sneaking into other people's minds is as easy as hooking yourself up to them and going to sleep, Dom Cobb (Leonardo DiCaprio) is an ace extractor who makes a living by stealing deep-seated thoughts and secrets out of his clients' corporate competitors. Missing his children back in the U.S. and constantly haunted by the tragic death of wife Mal (Marion Cotillard), for which Cobb has been named a prime suspect, he has little hope of ever being able to return to his homeland. Just as Cobb is preparing to take a hiatus, energy dominance magnate Saito (Ken Watanabe) pulls him back in with an offer he can't refuse: plant the idea into Robert Fischer Jr. (Cillian Murphy) to break up the empire of his ailing father Maurice (Pete Postlethwaite)—Saito's main rival—and Cobb will have all his charges back in America lifted. The process of inception, however, is far more complicated than a mere extraction, and for this he will need a whole crackerjack team to back him up: right-hand man and information specialist Arthur (Joseph Gordon-Levitt); architecture student Ariadne (Ellen Page), designer of the dreams; thief and forger Eames (Tom Hardy), and advanced chemist Yusuf (Dileep Rao).

Technically speaking, "Inception" is superlative. Visual effects are often stunning, even if the bulk of them have been given away in the trailers and television ads. A scene where Ariadne tests her internalized architectural skills by folding a bustling cityscape on top of itself is a feast for the eyes, certain to leave viewers questioning, "How'd they do that?" The portentous music score by Hans Zimmer (2009's "Sherlock Holmes") is appropriately sweeping, capped with ominous horns that remind of the sounds made by the Tripods in 2005's "War of the Worlds" remake. Cinematography by Wally Pfister (2006's "The Prestige") is also first-rate, effectively capturing a wide array of locations, from Paris to Morocco to the snowy peaks of Alberta, Canada. Conceptually, the film is beyond impressive, too. Writer-director Nolan has concocted a humdinger of a story, even when details feel forced and disregardful. If Cobb succeeds at his assigned task, for example, how does Saito have the powers to simply make a call and instantly get all the U.S. charges against Cobb dropped? This is carelessly never explained and the audience is expected to buy into it just because Saito says he can do it.

Where "Inception" really gets into trouble, though, is its failure to reach its fullest—or even one-half of its—potential. Intellectually, it's not nearly as smart as it pretends to be, and emotionally, it's a dud. The only character who is adequately developed is Cobb, and even then it's only in how he relates to his wife and grieves her loss. A little sympathy is built up, but it's mostly due to the performance of Marion Cotillard (2009's "Nine") as ill-fated wife Mal, powerful enough to make one buy into the events that led to her death when they are finally revealed. Otherwise, Cobb is decidedly streamlined himself, never giving a thought or seeming to have a problem with the immoral, unethical implications of his profession. The rest of the ensemble is one-dimensional plot fodder, receiving no pasts, backgrounds, arcs, or more than one or two character traits. With the exception of possibly Robert Fischer Jr., the conflicted target of their inception scheme, and Mal, whom we learn about in generalities via Cobb, the rest of the people on hand are just names with faces. Without proper lives and souls seemingly existing beyond the pages of the script, they might as well be dreaming even when they're awake. Usually not one to skimp on the key importance of character in film, Nolan has lost his way here, tossing aside someone worth legitimately caring about in exchange for his concentration on empty razzle-dazzle.

Also immensely disappointing is Nolan's scarce understanding of how the dream world works and his inability to externalize them in front of the camera. If Ariadne's job is to create the surroundings of someone else's dream—the look, the setting, the very architecture of the streets and buildings—then is it really still the dreamer's own? Also not taken into account are the hidden mysteries of the subconscious and the surprises it can frequently pull. How can Ariadne so easily control every aesthetic aspect of a dream, and every time? How can Cobb pull Mal into literally all his dreams? Sure, there's such a thing as recurring dreams, but not to this extent. These are inexcusable leaps in basic logic that no one bothers to explain. How often have you woken up from a dream or nightmare and questioned how something like that could have come out of your own mind? Dreams feature constant abstractions and surrealistic touches—"Inception" only passingly acknowledges this—and most of the time their subject matter is out of our hands. Here, almost every dreamscape not only looks too real, but like the setup for a stock action movie sequence. They are nearly devoid of subversiveness and, most grievously, of brazen creativity, which the visualization of dreams demand. They feature none of the emotions and feelings dreams cause—fear, elation, sadness, arousal—and are rendered outright impostors next to way superior, far more accurate films set in dreamlike states, from 1961's "Last Year at Marienbad" to 1984's "A Nightmare on Elm Street" to David Lynch's 2006 masterpiece "Inland Empire." Those are movies this one could only, well, dream of being.

Acting-wise, Leonardo DiCaprio (2010's "Shutter Island") can do no wrong; even when the films themselves leave something to be desired, he is able to find the truth within his characters. Such is the case here. As Dom Cobb, DiCaprio is so effortless at what he does that it's easy to take his seamless talents for granted. With that said, the role isn't fleshed out as much as it should have been and he never really gets a chance to do anything other than look morose and conflicted. The other cast members are across the board strong, which makes it all the more painful that they are so undernourished as characters. Joseph Gordon-Levitt (2009's "(500) Days of Summer") is straight-faced and serious as Arthur, whose sole centerpiece is a fight that defies gravity; Ellen Page (2009's "Whip It") brings willing curiosity and that's about it to Ariadne, serving as the voice of the audience as an outsider who asks questions and receives long monologues of exposition in return; and Cillian Murphy (2007's "Sunshine"), as Robert Fischer Jr., effectively captures the inner struggle of a man who believes his dying father always thought of him as a disappointment.

"Inception" culminates in an extended climax simultaneously set on four different dream planes, one deeper than the next. It's a neat idea, to be sure, with each one further down the rabbit hole coinciding with an increased timeframe, but taken as individual sequences they are all underwhelming and derivative. The hallway fight scene involving Arthur belongs in 2003's "The Matrix Reloaded," where it was done better and featured more innovation; the snow jet chase reminds of more veritably exciting set-pieces from 1993's "Cliffhanger" and 2002's "XXX," and the most subterranean level seems to steal shots wholesale from the early moments of 2004's "The Day After Tomorrow." Besides being imitative of past action efforts, the film gets so bogged down in its narrative construction that it never quite builds momentum or reaches the ramped-up pacing necessary to thrill as it should. Furthermore, it's awfully difficult to care too much about the outcome when there isn't a concrete dramatic connection to cling to. As opposed to 1990's similar, more provocative "Flatliners," wherein a group of med students grow obsessed with exploring the afterlife by stopping each other's hearts for minutes at a time and are subsequently haunted by the ghosts of their pasts, the characters in "Inception" cling to illusions as if they were drugs and come out of the ordeal learning virtually nothing about themselves. Meanwhile, many of the unique qualities of dreams remain frustratingly untapped. More concerned with maneuvering among its convoluted narrative to appease the mainstream than plumbing the many different layers that make up a person's wakeful and sleeping hours, "Inception," as a whole, barely scratches the surface.