THERE WAS a time when a film like Hancock, a Will Smith adventure about a drunken, depressed superhero, would have been described by screenwriters as "a movie I'd give my left nut to rewrite." After 10 years of batting around in development hell, the wreckage of Hancock's once-promising script is more interesting than any of the literal wreckage its titular superhero maudit leaves in his wake. They needed a needed a Michael Chabon to fix this situation. The third act is so desperately out of whack that it looks like the handiwork of M. Night Shyamalan himself. Our first sight of Hancock has him snoozing like a wino on a Los Angeles bus bench, plastic 1.75-liter bottle of whiskey by his side. He is roused from sleep for a drunken-flying mission to round up a carload of Vietnamese gangsters. The scene presents the kind of racism the urban audience loves dearly: the villains are Asian gabblers who really speak English if you force them to do it. Enraged by the thugs pulling guns, Hancock impales the get-away car on the needle of Hollywood's Capitol building. Later, in one weary moment of altruism, Hancock rescues a PR man called Ray (Jason Bateman) from a train collision. In return, Ray asks Hancock to come to his house for a home-cooked meal, to the delight of their son, Aaron (Jae Head). The superhero is a true boor ("Ya got a toilet?"). Still, Ray urges his wife, Mary (Charlize Theron), to be tolerant: "Do you want him to kill us all?" Ray is an altruist himself. We catch him in a meeting, trying to give the board of a pharmaceutical company a face-lift. He has an idea for a heart-shaped logo it can display, to symbolize its charitable contributions.

Under Ray's guidance, Hancock makes a public apology and allows himself to be thrown into jail to answer for his 600 outstanding subpoenas. Gradually, he gentles under the solitude and 12-step meetings. When Hancock gets out, though, the immortal can't help being helplessly attracted to Mary.

The casting works, allowing Smith—usually a chilly, arrogant figure onscreen—to slowly warm up before us, to straighten up and fly right. The way Smith plays Hancock, a flailing, superpowered bum, recalls the best moments in Superman III, of Christopher Reeve's kryptonite-drunk scenes. There's a certain W.C. Fields appeal in the heavy boozing and the roughing up of bratty children. Still, director Peter Berg can never figure where he stands. And as an actor, Bateman is too slick for the kind of bleeding-heart I think Berg means the character to be. We never know whether his plan to get corporations to rehab their image is heartfelt or idiotic. The film's last scene, using Ray's logo, is not only idiotic: it's creepy. For the camerawork, Tobias A. Schliessler was brought in, probably because he worked with Berg on TV's Friday Night Lights. The small-camera photography offers an interesting approach when joined with John Dykstra's special effects; it's a Cloverfield-type spectacle: blink and you miss it. This approach functions best in the dinner-table scenes, where Hancock simmers in dislike of the puny humans. And when Hancock splits a locomotive in two, the camera watches the dominoing of boxcars from a nice distance, through a telephoto lens. The too-quick-for-the-eye scooping up of gunmen, one by one, during a hostage situation makes for an invigoratingly tight sequence.

And Berg is deft with the comedy of rehab. Chastened by therapy, Hancock asks a wounded policewoman, Antioch Rules–wise, whether he can touch her before he airlifts her to safety. Hancock is a mystery to others as well as to himself. ("They're using 50-caliber bullets," a cop tells Hancock. "I don't know if that matters to you.")

This scene with the 50-caliber bullets introduces us to the villain "Red," played by Eddie Marsan. Marsan is a snarling-whippet version of the evil Ralph Fiennes–style greyhound. But we get Red's backstory from an overheard TV broadcast—he's some sort of Nietzschean psych professor from S.F. State, it turns out—rather than from anything he does or says. Like Lex Luthor in the Superman movies, Red compromises his brilliance by hiring oafs. But the exact relation of the criminal world to Hancock is also vague. Hancock has been around for 80 years by his count, and yet no one has figured out a more scientific approach to getting rid of him, or figured out not to make him angry? Questions stack up high when the third act conjures up a bride for this super–Frankenstein's monster. The tactic looks so wonky that any screenwriter watching will itch to fix it. And it's also a slap to the women in the audience.

The wave of films treating women like walking incubators continues in Hancock. These days, a female character's life-or-death ordeal consists of watching a pregnancy tester. We even had Steve Carell's Maxwell Smart needling 99 about her "dusty uterus." When Hancock's other half reveals herself, we learn that all her godlike superpowers and duty to aid humanity come down to this most important mission: helping a single dad pick out diapers for his toddler.

HANCOCK (PG-13; 92 min.), directed by Peter Berg, written by Vincent Ngo and Vince Gilligan, photographed by Tobias A. Schliessler and starring Will Smith and Charlize Theron, opens July 2.

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