PARK CITY - One of the most justifiably adored romantic comedies of all time is "When Harry Met Sally," and in the quarter-century since its release, there have been many films that have been compared to it, normally coming up short. It's such a well-made movie that I resist making comparisons to it normally because I think it does other films no favors. So when I say that Leslye Headland's "Sleeping With Other People" is a 21st century worthy successor, that is very high praise.

Certainly there's nothing new about the notion about sexual tension between people who are "just" friends, and there's no groundbreaking insight here that elevates "Sleeping With Other People" automatically. Instead, it's a cumulative thing. There is real wisdom and honesty in every moment of the film, and that's refreshing in a genre that is built largely on fantasy every bit as disconnected from our reality as any superhero film. Romantic comedies have a bad name today, and they should. Most of them are pandering junk that reinforce gender stereotypes, and they set up these unhealthy ideas about how we're supposed to treat each other in relationships. I am frequently amazed when I see one of these films that is built entirely on the premise that everyone lies to everyone else, and yet we're still supposed to care whether or not they find love with one another. The mere notion of what "love" is in movies is often so twisted that I don't recognize it.

What's interesting here is that both Lainey (Alison Brie) and Jake (Jason Sudeikis) are messes when they meet, and throughout the film, they each make plenty of bad choices and they are not particularly great about how they behave to each other or to other people. Even so, Headland has tremendous empathy for them both, and even when they make those terrible choices, we understand them. It's easy to recognize many of my own mistakes in the way these two relate. They meet originally in college, and their initial encounter ends with them revealing to one another that they are both virgins. They solve that problem, and we jump forward ten years to find the two of them, both living in New York, but they haven't seen each other since that night.

Jake has become a shameless womanizer, while Lainey is still focused on Matthew (Adam Scott), an OB/GYN who she has been in love with since college. Jake intentionally keeps people at arm's length, knowing that he's charming enough to get what he wants from women and knowing that he's exceptionally good at blowing things up when he wants someone to go away. Lainey's focus on Matthew has kept her from pursuing any other relationships, even though Matthew has a fiance (played in a few brief scenes by "Inherent Vice" star Katherine Waterston), and there's a sense that he has always treated her as second-rate, someone to keep on the side, and that she has for some reason allowed that to become normal.

When Jake and Lainey reconnect, it is, of all places, at a meeting for a sex addicts support group. Instead of immediately reconnecting sexually, their shared past and the insane way they bump into each other leads to conversation and an immediate emotional ease with one another. They make a decision to specifically not sleep with each other, even going so far as picking a safe word to use if they start to feel any growing sexual tension.

I recently saw a still-unreleased film with Alison Brie in it, and part of what bummed me out about it was seeing how little they gave her to do. I think Brie has proven between "Mad Men" and "Community" that she has a remarkable amount of range, so I'm glad that Headland gave her such a rich lead to play. Brie more than rises to the challenge, too. She attacks the role with everything she's got, from the way she's introduced to the genuinely unsympathetic moments that she steers directly into to a sure-to-be-remembered scene where she is on ecstasy and teaches an entire birthday party full of nine-year-olds how to dance.

One thing that this film does that "When Harry Met Sally" did not is it gets into the particulars of sex, and there are several scenes here that are genuinely hot. No nudity, but then again… that's not what makes a great sex scene memorable. What this gets right is the way certain details can become almost overwhelming in that moment of abandon. The sound of someone's breath. A vein standing out in someone's neck as their entire body seems to contract. A hand on the back of a neck. There's a reason Lainey can't quit seeing Matthew, and so often, our bodies tell us one thing while our heads tell us something different. We are powerless at times to these deep primal drives of ours, and "Sleeping With Other People" understands all the different ways that can play out in relationships.

Jason Sudeikis seems to be one of those guys who is always huddling on the verge of stardom. His biggest hit to date, "We're The Millers," certainly leaned heavily on him, but I think that whole campaign leaned on the premise more than him as the lead. And the "Horrible Bosses" films are about the trio, not just him. I think my favorite thing he's done prior to this was his season of "Eastbound & Down." The performance he gives here is more real and more grounded than anything he's done so far, and I have to give it up fodr the way he seems to fill a particular comic archetype that's been missing for a while now: young Chevy Chase. When he was his best, Chevy could make it seem like he utterly didn't care what happened next. It's little wonder they're talking about casting him as Fletch in a new film.

Lainey declares herself celibate for a year to try to help shake her cycle of behavior with Matthew, while Jake continues dating, constantly pushing his boss to go out with him. Andrea Savage and Jason Mantzoukas are friends with Jake, and as soon as they see Jake with Lainey, they are certain that Jake's found the one. Savage and Mantzoukas are perfectly utilized here, and there are plenty of scenes where each of them get a chance to really rip, including a sequence played during the closing credos that is solid gold.

This movie plays on the surface as a rude, profane, brash, wild little thing that will make you laugh constantly. Underneath that, though, there are plenty of things that the movie deals with that are very serious, very real. The movie isn't so much a will-they-won't-they relationship picture as it is a movie about how we learn to love people and how important it is for all of us to be able to find that love.

I love that Jake refers to Lainey as "my best friend." At 44, I am just starting to learn to date again and considering it's been 15 years since I last had to date at all, I feel like Moonwatcher freaking out and throwing his bone at the Monolith. Everything feels new and vaguely terrifying. People use technology in all sorts of ways to search for love, and the last time I was single, I didn't even own a cell phone. Now if you're looking to meet someone, you have to put technology to work for you with apps and Snapchats and your Twitter feed, and you try to treat the Internet like a gigantic catalog where you're ordering up the person you want to be with. When you do that, you open yourself up to all sorts of things, and not all of them are good things to be involved in.

These days, there is a person in my life who just plain makes me happy. It's far more important to me that I call her my friend or even my best friend than any other label that might define the relationship we have, because I can talk to her about anything and because her happiness is important to me, just as my happiness appears to be important to her.

That's love enough for me, and it helps me clarify what I need and want. I am desperate to stop making old mistakes over and over and over, and that's exactly what Jake and Lainey are looking for, even if they're not quite in sync about what new mistakes they could make. Life rarely lines up the way we want it to, and Headland perfectly captures the way it feels every time life throws us a new curveball. The language is frank and direct, and Headland's got a very strong hand as a director thanks to all the hard work that Headland put in as a writer first. She's more confident as a filmmaker now than when she made "Bachelorette," and I hope this is just one of many, many Leslye Headland films we're going to get to see.

"Sleeping With Other People" made its premiere this week at the Sundance Film Festival.

A respected critic and commentator for fifteen years, Drew McWeeny helped create the online film community as "Moriarty" at Ain't It Cool News, and now proudly leads two budding Film Nerds in their ongoing movie education.