In recent interviews, teen superstar Hilary Duff has mentioned that she has been offered more mature film roles—"pregnant girls with crack habits," as she describes—but has opted to turn them down. Her reasoning is that there is plenty of time to grow into those types of adult-oriented parts, and it would be a betrayal to her teen and preteen fanbase who look up to her as a positive role model. I've got news for Hilary: she's not going to be a teenager forever, her fans will eventually outgrow her, and starring in trite, empty-headed garbage like "Material Girls" is far more insulting to her prospective young audience than taking on an edgy indie flick that just might be able to show her range as an actor. If the 18-year-old Duff doesn't start choosing her projects more carefully, her movie career could be dried up by the time she's legally old enough to drink.

For the first time in any major capacity, Hilary is joined onscreen by real-life older sister Haylie in a premise that practically demands to be ridiculed. Tanzie (Hilary Duff) and Ava Marchetta (Haylie Duff) are the ultra wealthy heiresses of Marchetta Cosmetics, formerly owned by their dearly departed father. They've got the world at their fingertips and their only stress in life is picking out a fabulous designer outfit to wear to clubs and special celebrity events. All of this changes when accusations fly that the cosmetic line causes severe skin damage and rival company owner Fabiella (Anjelica Huston) wants to buy them out. Suddenly penniless and without a home—their mansion burns down in a careless accident—Tanzie and Ava must taste a spoonful of cold, bitter reality as they set out to investigate the suspected false claims and save their company. In the meantime, they come to realize that money doesn't buy the same type of happiness that love does.

Whose terrible idea was it in the first place to pair up Hilary and Haylie Duff as shallow and pampered rich girls bearing striking a resemblance to Paris and Nicky Hilton, as well as Mary-Kate and Ashley Olsen? Didn't these two gals know that playing parts like this would only invite criticism upon themselves? Were "Material Girls" smart or fresh or truthful at any turn, all could be forgiven and viewers might have had a younger version of 1997's irresistible "Romy and Michele's High School Reunion" on their hands (granted, Romy and Michele weren't rich, but never mind). Instead, "Material Girls" is a wasteland of viable cinematic material interspersed with comic zingers so rare that they seem to succeed by accident.

That a film of such ineptitude is directed by Martha Coolidge (2004's "The Prince & Me"), who once helmed the classic 1983 teen comedy "Valley Girl," and co-stars acting royalty like Anjelica Huston (2004's "The Life Aquatic") in a nothing role, signifies how far the greats can fall. "Material Girls" is sloppily edited, with full narrative threads being forgotten on a whim and supporting characters dropping in and out of scenes at random. The ADR work is just as amateurish, with moving mouths not matching speech and frequent overdubs suggesting that this started off with a planned PG-13 rating. The cinematography by Johnny E. Jensen (2000's "The Ladies Man") is dreadful, with washed-out colors, too much soft focus, and a grainy aesthetic sheen that works adversely with what is supposed to be bubbly and bright in tone.

And then there is the stuff—pratfalls, one-liners, fish-out-of-water scenarios—that passes for humor, nearly all of which was thrown into the packed theater audience and returned by the faint sounds of crickets chirping. A scarce few barbs and moments squeak through and garner chuckles in the ever so slightly better second half—a Courtney Love joke here, a stint in a jail cell between Tanzie and three butch lesbian hookers there—but they are useless in the midst of a screenplay by John Quaintance (2006's "Aquamarine"), Jessica O'Toole and Amy Rardin that, no matter how much post-production tinkering went on, couldn't possibly have been good in any draft.

It's obvious why Hilary Duff (2005's "The Perfect Man") and Haylie Duff (2004's "Napoleon Dynamite") share a natural and easy rapport together as Tanzie and Ava Marchetta—the actresses are siblings, after all—but their individual performances range from merely competent to rudimentary. They are photogenic when their faces aren't made up to look like a transvestite's on Halloween night, but their unrelatable characters' growth into more responsible and caring adults isn't developed in a believable way. The best scenes in the picture are not between sisters, but the ones ripe with romantic tension between Haylie's Ava and the pro-bono lawyer who agrees to represent them, Henry Baines. Henry is played by, of all people, young veteran actor Lukas Haas (2005's "Brick"), who gives the film's most interesting performance even when looking like he'd rather be anywhere but there.

Like the Madonna song on which it is based (and from which Hilary and Haylie perform an inferior cover version), "Material Girls" is about a pair of women who are driven by their hunger for fame, money and consumerism. Not exactly the most ideal people to have as protagonists in a movie targeted at girls between the ages of 9 and 14, but there you have it. Oh, and while on the subject, why should an audience care at all about Tanzie's and Ava's welfare when they pitch a fit over being offered "only" $60-million a piece for their shares in the Marchetta cosmetics company? Boo-freakin'-hoo. "Material Girls" stays true to its name, all right, but there's no reason the film also had to be an embarrassingly unfunny and aimless chore to sit through. The Duff sisters have screen presence; now what they need is a better taste in scripts.