In some ways, Rob Reiner’s 1989 rom-com plays the role of organized religion for this most divisive of cinematic sub-species: It’s either the cause of, or the solution to, everything that’s wrong. Because while Reiner and Nora Ephron hardly invented the idea of combining a love story with humor, they created a blueprint for the way an entire generation of filmmakers and screenwriters would tend to approach the genre. And while a hundred different efforts have been made to copy the formula, too few of them get beyond the superficial elements. The charms—and disappointments—of Going the Distance give us a chance to examine what to include, and what to leave out at your peril.

The divider. Something has to keep our protagonists apart for 90 minutes or so, even if we know in our heart of hearts they’ll end up together. First-time screenwriter Geoff LaTulippe finds a perfectly plausible one after Garrett (Justin Long) and Erin (Drew Barrymore) meet-cute in a New York City bar and instantly connect over their shared love of Centipede and bar trivia. Garrett is an entrenched New Yorker working in the record industry; Erin is a summer intern at a newspaper, fixing to head back to California to finish her graduate degree in a matter of weeks. Convinced of their connection, Garrett and Erin impulsively decide to continue their relationship long-distance, even if that means sporadic cross-country visits and texting taking the place of regular one-on-one time.

The confidantes. Bruno Kirby and Carrie Fischer taught us in When Harry Met Sally … that our protagonists each need someone with whom to share thoughts about how the relationship is going. Here, Garrett gets his weird roommate Dan (It’s Always Sunny in Philadelphia’s Charlie Day) and co-worker Box (Saturday Night Live’s Jason Sudeikis); Erin gets her tightly wound, married older sister Corinne (Christina Applegate). And all involved provide great comic-relief moments like Box’s sexual-bucket-list rationale for wearing a mustache, and Corinne’s horrified response to catching Garrett and Erin having sex on her dining room table. The supporting players need to provide the eccentricity, so that we can grow to care about main characters who aren’t too strange. Which brings us to …

Our lovebirds. So much depends on believing in the pairing of the two stars—but it isn’t just about whether they’re cute together. Barrymore and Long have a solid, if unspectacular, chemistry, and it’s easy enough to root for them to find their happily ever after, but the screenplay misses opportunities to fully flesh out Garrett and Erin. The early indication is that Garrett is a commitmentphobe who needs to do some growing up, but Going the Distance doesn’t explore the obvious question of whether a long-distance romance provides an easy barrier between him and a deeper relationship. Nor is Barrymore quite deft enough to convey the conflict of a woman who appears ready to make the same love-over-career decision that derailed her life once before. At the halfway point, when the story should be wrestling most with what our characters need to learn to be ready for happiness, Going the Distance starts to feel like it’s running out of steam.

A little edge. Here’s what people too easily forget about When Harry Met Sally …, and what director Nanette Burstein (American Teen) and Going the Distance refreshingly remember: Safe and fuzzy isn’t always all that funny. Where most rom-coms live comfortably in the PG-13 zone that won’t alienate its typical target audience, Going the Distance is a legit R, raunchy in ways—like Sally’s legendary diner faked orgasm—that are perfectly appropriate for a modern relationship story. Instead of serving up predictably cutesy moments of embarrassment, we get stuff with a little stank on it—the awkwardness of phone sex, or how to deal with that roommate on the other side of your thin wall. There are uneven patches here, but when it comes to recognizing that you can make this formula work without making it insipid … I’ll have what they’re having.

GOING THE DISTANCE