The messy breakup that is the subject of 500 Days of Summer could have been avoided, had someone only told Tom (Joseph Gordon-Levitt) that a shared love for the Smiths does not guarantee a functional relationship. But in this relentlessly hip exploration of the mating habits of the creative class, the Morrissey-loving Tom's a goner from the moment he hears Summer (Zooey Deschanel) croon "To die by your side is such a heavenly way to die" in that clotted little voice of hers.

In the 500 days the film spans, a familiar arc is described: Tom and Summer date; Tom gets too attached; Summer breaks it off; and Tom lapses into the sort of melodramatic, self-pitying behavior that seems utterly ridiculous when engaged in by anyone but one's self.

But wait. Problem: Breakups are depressing, and Gordon-Levitt and Deschanel are far too adorable to squander on melodrama. So first-time director Marc Webb skirts the bummer factor by shuffling his story's chronology, splicing together out-of-order scenes from their relationship to chart its dissolution. Other gags further cushion the film's potential emotional impact: There's split-screen, a totally superfluous narrator, a musical number, and Deschanel's complete inability to register emotional depth—all of which collude to render a gut-ripping breakup as mild indie entertainment.

Tom and Summer's relationship is as realistically described as any I've seen, and downtown Los Angeles is virtually unrecognizable, shot gorgeously in shades of gloom. But there's so much here that's supremely annoying: An impossibly grating little sister doles out romantic advice. Tom works at a greeting card company, which lends itself to just as many low-hanging scenarios as you might expect. And worst of all, the film doesn't have the balls to follow through on its promise to present a realistic look at modern love. No, 500 Days is a fairy tale, and it's all the more frustrating because it pretends that it isn't.