To give credit where credit is due, Something Borrowed imagines a scenario weightier and more serious than most romantic comedies. The film, based on a book by Emily Giffin, starts out in surprisingly mature territory. Ginnifer Goodwin (late of HBO’s “Big Love”) is Rachel, a wallflowerish lawyer stuck between a rock and a hard place. Seems her brash, center-of-attention BFF Darcy (Kate Hudson) is about to be married to hunky nice guy Dex (Colin Egglesfield, who did soap opera duty on “All My Children” and the new “Melrose Place”). The problem? Rachel has had a crush on Dex since college. But she’s always been too wimpy to do anything about it, quietly conceding the romantic battle to her outspoken gal pal.

One drunken night, however, Rachel and Dex hook up. This leaves them even more confused than before. What is Rachel supposed to do now? Stay with Dex? Break up her best friend’s impending marriage? Which is greater: her love for Dex or her love for Rachel? It’s a thinker, and Something Borrowed runs well with this conundrum for a while.

Unfortunately, at the end of the day, Something Borrowed is just another romantic comedy and stumbles into most of the same traps as others of its ilk. Sooner than later, the characters are competing with the cast of any horror movie with a Roman numeral in the title for the designation “worst decision-makers ever.” If any one of the characters in this film were capable of saying one honest thing to anyone at any time, their problems would be solved.

The cast, at least, is well-chosen. Goodwin does shy and cute just fine. Hudson is certainly appropriate as the self-centered life-of-the-party girl. Egglesfield is ... hunky. John Krasinski (from “The Office”) even gets to tag along in the “Duckie” role as Rachel’s non-sexually-threatening male confidant to whom secrets can be regularly imparted. I was actually prepared to feel some sympathy for these lovelorn characters; but the script turns them into politicians at election time, waffling back and forth on important issues so many times it’s impossible to tell where they stand. (Sleep with your best friend’s fiancé once and you’ve got an interesting moral problem. Sleep with him and break up with him three times and you’re just wishy-washy.)

Ultimately, it’s hard to figure out what any of these people are doing together. Dex and Darcy as a couple? Unbelievable. Darcy and Rachel as best friends? Unlikely. The sad thing is, if these people had been given realistic characteristics—perhaps they were in the novel—this could have been an absorbing situation. Instead, all difficult decisions are rendered moot. Darcy is presented as such a greedy, loudmouthed wench, she deserves to have her fiancé taken away. On the other hand, Dex is such an indecisive wuss, he’s not worthy of snatching. And Rachel? She’s so much of a self-pitying victim, she needs therapy, not a boyfriend.

The film is passingly directed by Luke Greenfield (who gave us Rob Schneider’s The Animal, for what that’s worth). But the guy can’t seem to ramp things up properly. Every time something interesting threatens to happen—as in a secret-spewing game of beach badminton—the film pulls back. It never takes anything to the next level. The setting, for example, feels incredibly claustrophobic—rarely moving from Rachel’s apartment or wandering out of sight of the same 10-by-10 chunk of Central Park real estate. It’s the live-action equivalent of recycling the background drawings in a cheap cartoon.

There are good moments of humor sprinkled throughout Something Borrowed. There are hints of serious, painful drama. But it’s all so chopped up and scattered. None of it ever gels. Shame, really. This could have been an interesting romantic comedy. Instead, it’s a lot old, very little new, plenty borrowed and very likely to leave audiences blue.