Who's In It: Joseph Gordon-Levitt, Zooey Deschanel
The Basics: He's a greeting card copy writer who's given up his dreams of being architect. She's the kind of charming, pretty, hypnotizing indie-lady who ensnares young, cardigan-wearing Smiths fans into her trap of aloof semi-romance. And since their 500 days (she's Summer, by the way--the 500 days are just that, a finite relationship time allotment) involve him being so smitten and overwhelmed by her that he actually finds himself involved in impromptu musical numbers with blasting fountains, marching bands, dancing street people and twittering cartoon birds landing on his finger to sing along, naturally he's also the one who's doomed. That's the moral, really: the one who loves more is the one who gets dumped.
What's The Deal: If you took this non-chronological narrative and poured it into the shape of how an actual relationship begins, falters, resumes and then ultimately dies, you'd have a really conventional story with a sad(ish) ending. But the zig-zag of the action, the fantastical elements involving animation and the above-mentioned musical number, the split-screen where you see fantasy and reality played out side by side, the drop-dead attractiveness of the leads, the love the movie has for its own unusually urban version of Los Angeles and the dogpiling of young culturally aware signifiers (if you know all the words to "Please Please Please Let Me Get What I Want" then you know exactly what's going on in the scene where they play it) all conspire to make it more than the sum of its parts. You've seen this movie before (just usually with a fakey big-kiss ending; extra points here for the blunt honesty about breakups) but this one is just right for Right Now.
Not-Exactly-Secret Weapons: It helps that both Joseph Gordon-Levitt and Zooey Deschanel are good actors, really aware of what their job is. And it doesn't hurt at all that they're really cute, expertly wardrobed and art-directed to the moon and back (check out ZD's insane blue color-coding throughout, right down to the wallpaper in her apartment and the ribbon in her hair). But it's really the cinematographer who makes you want them for yourself and for each other. She's shot in a way that would lead you to believe that she could enslave entire armies of young literate heterosexual men and he's running a close second. It's actually worth seeing if for no other reason than to watch how these two are packaged and sold.
About That Musical Number: Done to death. But for some reason it's always a surprise. And this one is witty and funny and joyful and almost makes you wish the entire film were like that.