With its foreboding title, "There Will Be Blood" makes a promise that it doesn't keep. That is not to say that the film is totally bereft of the red stuff, or even that it's a horror movie (at least in the conventional sense). What writer-director Paul Thomas Anderson (he of 1999's "Magnolia" and 2002's "Punch-Drunk Love"), in the first stumble of his career as a filmmaker, does not fulfill is the suggestion throughout that his leisurely paced, gorgeously mounted period epic is leading toward an explosive conclusion. Instead, the ending takes an awkward turn toward goofiness and culminates on a underwhelmingly bitter note that doesn't add up to much.

In turn-of-the-century central California, ambitious prospector Daniel Plainview (Daniel Day-Lewis), searching for gold and silver, strikes an oil cashcow and turns it into a business. With his appetite whetted but insatiable, he and 9-year-old son H.W. (Dillon Freasier) move on to the Sunday homestead when one of their sons, Paul (Paul Dano), pays Daniel a visit in secret with claims that oil resides on his family's property. Under false pretenses and low rates, Daniel obtains the proper permissions to begin drilling, an act that will make him a fortune at the expense of alienating everyone—even flesh-and-blood H.W., who is injured and goes deaf in a freak accident—around him. His biggest adversary steadily becomes Paul's pious twin brother Eli (Paul Dano in a dual role), an evangelist who is adamant that Daniel is deceiving the community.

If there is a reason to see "There Will Be Blood," it is for Daniel Day-Lewis' (2002's "Gangs of New York") fiery, mesmerizing performance as Daniel Plainview. Simply put, he is so good it's scary, disappearing completely into a ruthless and unforgettable character whose very soul is eaten up by his unquenchable greed. Watching Daniel's transformation from a ne'er-do-well single father into a sociopathic monster, the shell of his former self all but obliterated by his very hatred for everything but money, is appropriately ugly and disturbing, and Day-Lewis doesn't so much as bat an eyelash in his note-perfect portrayal of him. If this Oscar-bound turn is one of the strongest of the year, it only calls more attention to the weaknesses around him.

Loosely based on the 1927 novel, "Oil!" by Upton Sinclair, writer-director Paul Thomas Anderson admirably approaches "There Will Be Blood" with a keen eye for visual details and individually riveting character moments. The opening hour of setup is the most successful segment, and Anderson is so assured in his dramatic beats and exacting mise en scene that one barely notices that fifteen minutes have gone by with no more than a word or two of dialogue. While his talent is not to be denied, Anderson's subjective departure from his typical Los Angeles setting and creative departure from flashy camera movements turns out not to suit him as comfortably. The second act is especially slow-going, taking twice as long as need be to get his points across and setting up conflicts that are never resolved. When Daniel vows to slit the throat of a Standard Oil bigwig not once, but twice, it is expected that there will be a payoff. It never comes. This same sort of thing occurs again and again as the story's interest ebbs and flows but ultimately runs in circles. Meanwhile, other central characters, particularly that of Eli Sunday, vanish for such long periods of time that it exposes the screenplay's and/or editing's slack unevenness.

Technical credits are top-of-the-line, including Robert Elswit's (2007's "Michael Clayton") lush, atmospheric cinematography and Jonny Greenwood's (he of Radiohead) mood-drenched score. The music is eerie, bombastic and beneficially off-balance, like something out of a horror film. Performance-wise, while Daniel Day-Lewis runs the show, Paul Dano (2006's "Little Miss Sunshine") ably goes head-to-head with him as the gospel-spouting Eli Sunday, and young newcomer Dillon Freasier is staggeringly expressive as H.W., who doesn't have a lot to say and doesn't need to.

The most powerful moment in "There Will Be Blood" is a late scene not of physical violence, but of the emotional kind, as Daniel comes face-to-face with his estranged, now-grown son. Without giving it away, it is a sequence of immense rawness, so upsetting that one almost wants to shut out the sound of the words being exchanged on-screen. Disappointingly, it is followed up by a denouement that is poorly staged, almost unnecessarily comic, and off-puttingly anticlimactic. When one goes to see a film called "There Will Be Blood," particularly one made by Paul Thomas Anderson and as promising and serious-minded as this, it is natural to expect that it will add up to more than a farcical chase around a bowling alley.