Eliza Coupe: We had a laugh attack that was honestly … I don’t know. We had another one —

Damon Wayans Jr.: We have one like every —

Eliza Coupe: Well, during the scene with the workout stuff where Pally and I decided to make each other smell certain things.

Damon Wayans Jr.: Oh man! That was crazy! Don’t tell them that!

Eliza Coupe: I’m not even going there with that one. It was one of the grossest things in the world. But funny.

Damon Wayans Jr.: Basically we just laugh a lot together.

Eliza Coupe: All the time.

In the taxonomy of sitcoms there are many species. There are workplace comedies and relationship comedies, romantic comedies and anarchic comedies. Showtime even harbors a particularly rare and delicate genus, the unfunny comedy. But in the same way the Sham-Wow guy and Shamu are both mammals, all sitcoms are really one thing: family comedies. It’s a secret sauce as basic and unchanging as what McDonald’s slaps on your Big Mac: Successful sitcoms are about clashing personalities forming lifelong bonds. The characters bicker, but really they love, just like families or particularly liberal cults. If the people onscreen don’t enjoy spending time together, then the audience won’t enjoy it either. The accumulated quirks, Segways, and unseen wives should serve to accentuate the chemistry, not distract from it. In other words, it should always be about the guys and the girls. Never the pizza place.

With apologies to the civic-minded drones of Pawnee and the extended Dunphy clan, no televised chemistry experiment worked better this year than Happy Endings. The ABC comedy came into its own in its sophomore season, achieving a rare synthesis of humor and heart and, in the process, becoming so much more than the Friends clone it was dismissed as during its under-the-radar 12-episode run in the spring of 2011. (From late convert Alan Sepinwall’s early review: “If the show they were working on weren’t so flat and lacking in laughter, I’d actually feel sorry for the people involved with ABC’s Happy Endings.” Yoinks!) The initial criticisms had less to do with the show itself — the pilot, in which underwritten blonde Alex leaves underwritten bro Dave at the altar, throwing their more wackily drawn amigos into disarray, is actually quite charming — than with banter fatigue. Ever since Joey Tribbiani packed his bags for a short-lived stay in Los Angeles, networks have scrambled in search of the new Friends. And with good reason: Series about good-looking young people, amply armed with quips, condoms, and hair gel, tend to garner decent ratings, the right kind of viewers, and remarkably unairbrushed magazine spreads. And as most critics correctly, if sniffily, pointed out, Happy Endings is no Friends.

Zachary Knighton: We have so much fun with each other it’s ridiculous. We just really do come in and play every day. It’s crazy.

Elisha Cuthbert: It didn’t take us long to get into the crazy, either.

But here’s the thing: It took plenty of time for even Friends to become Friends. “NBC Sitcoms Make Thursday Less Funny” blared a Houston Chronicle headline from September 1994 (or was it a Grantland headline from last week?). People tend to remember beloved sitcoms at their peaks or just past it, not how much work it took to get there in the first place. To wit: Cheers was the lowest-rated show on television its first season, and Claire, Seinfeld’s sassy waitress, has been scrubbed from history more effectively than a John Calipari NCAA season. The key difference between sitcoms and families is that in the former, intimacy isn’t something you’re born with. It has to be developed. The joy of Happy Endings’ second season has been in watching this familiarity form in real time. Instead of doubling down on what was working at the end of last year — Eliza Coupe’s crazy eyes, Damon Wayans Jr. and Adam Pally’s burgeoning, multiracial metrosexual bromance — the producers dug deeper to fix what wasn’t. Now, formerly stiff straight-man Zachary Knighton, and especially intentional comedy newbie Elisha Cuthbert, have been fully integrated into the cast, finding Navajo-Indian and baby-back-rib-fueled laughs that not even their agents could have suspected they were capable of. All of this, plus racist parrots, cursed birthdays, and an incredible cocktail called the Whore’s Bath. But what makes a romantically charged twentysomething (you’re welcome, Penny) sitcom exhilarating isn’t zeitgeisty riffing or reheated Chandlerisms. It’s the thrill of watching skilled performers fall in love. Not with an endless stream of slacker bros and reliably shirtless former Texas con men, mind you, but with each other.

Adam Pally: The two of us met a long time ago, in New York. Would you say there was sexual tension?

Casey Wilson: No.

Adam Pally: You wouldn’t?

Casey Wilson: You have a wife! This is embarrassing … I was always attracted to Adam and then was shocked when I found out he was engaged because he’s so young.

Adam Pally: We met and had flirtatious bits onstage. Then you went and got SNL and I got married.

Casey Wilson: Both have failed.

Adam Pally: [Laughing.] Correct. Both have failed since.

A visit to the Happy Endings set in late winter put that intramural love on full display. I arrived under the impression that this would be a casual call, a chance to observe and chat between takes. But a Jane Kerkovich-esque crewperson had other ideas. Within moments, he’s deposited me at Penny’s breakfast bar with a rigid schedule of seven-minute drop-ins from succeeding pairs of cast members. Any sense of journalistic remove is immediately threatened because, unlike most actors, these six are exactly as you’d expect them to be in real life. Damon Wayans Jr. and Eliza Coupe arrive first, clad in attractive winter outerwear. (The episode being filmed, later aired as “The Butterfly Effect Effect,” concerns their characters, Brad and Jane, having their annual winter fight. It’s also the last episode of the season set in winter. Says executive producer Jonathan Groff, “It’s gonna be an early spring for Chicago. Coupe has crazy-great legs and should be in short skirts as soon as possible.”) It’s instantly apparent that this duo appears to have no off switch, egging each other on and collaborating on brilliantly dirty digressions like a game of X-rated Jenga. Wayans begins by dumping over a plate of what appear to be decorative yuppie balls of yarn while Coupe stands suddenly to close all of the cabinet doors, disturbed by their barrenness. (“Does anyone else have a cupboard thing?”) Her sight line pacified, Coupe finally settles in and answers a question about her fake marriage, tracing its insanely crackling chemistry back to the first time the two met. It was at the “pre-read” for the pilot, which, she’s quick to inform, is “where you can still get pregnant.” “That’s the clear stuff, right?” Wayans interjects. “Yeah,” says Coupe, nodding like a born-again in the first pew. “It’s the clear stuff. With just a hint of pigment. It kind of looks like this fake granite countertop with these little swirls.” Wayans giggles. “We’ve just been goofy bastards ever since.”

Pitched at a slightly less frenetic boil, Adam Pally (happily married, despite his joking) and Casey Wilson come across as the down-to-earth improv vets that they are, seemingly more interested in talking about their mutually forsaken hometown of New York than their breakout characters. (Even Happy Endings creator David Caspe is forthright about the early days. “The most developed characters in the pilot were Penny and Max. I knew who those two were. I kind of knew the others.”) “I think it’s the nature of TV,” Pally says through an artificial beard (an actual one that’s glued to his face, not, say, Sal’s wife on Mad Men). “You give something room to grow and it’s going to start to click. Not everything clicks from the pilot.” “Well, not everything is given the time,” Wilson adds. “Honestly, I think it’s like winning the lottery to get your show on-air for even that one episode.” If there’s a whiff of resentment over her unceremonious firing from Saturday Night Live in her answer, Wilson keeps it well-hidden.

Pally and Wilson are shepherded back to wardrobe grudgingly, still trading stories about lousy Lower East Side apartments and the even lousier Knicks (it’s pre-Linsanity) and replaced by the much more guarded pairing of Knighton and Cuthbert. Their reticence isn’t unexpected: The former’s résumé is filled with serious actorly striving (including a non-memorable stint on post-Lost loser Flash Forward), while the latter was posing in Maxim and being menaced by cougars back when David Caspe was still peddling animated installations to art galleries. But even from underneath Knighton’s low-fitted baseball cap or from behind the pint-sized Cuthbert’s shield of potential cold-having that’s either legitimate or a well-practiced defense against potential physical contact with dudes who make things like this, the enthusiasm is apparent. “It truly feels like we’re hitting our stride and really embracing each other,” Knighton says earnestly. “It feels like it’s a good place to be.” “I joke about it, but I was fine with being the straight guy because I was just glad to be here,” Cuthbert explains. “Now getting to do some funny stuff, it’s been such a highlight.” Indeed it has: The transformation of Cuthbert’s Alex from runaway bride to gloriously dim, dim sum-devouring troublemaker has been as fun to watch as it clearly has been for Cuthbert to play. “It’s hard to explain during a first season that you know the chemistry is there and that we just need time.”

Eliza Coupe: I will say this, and you may think it’s weird, but with him it’s totally effortless. Last night we did a scene, we didn’t even discuss it before, we just ran lines and did it.

Damon Wayans Jr.: Applause broke out afterwards.

Eliza Coupe: It was insane. It was, if I do say so myself, one of our best scenes. I’m just going to toot my own horn.

Damon Wayans Jr.: No, I agree!

Interviewer: Toot all you like.

Damon Wayans Jr.: TOOT IT!

At least for the day I’m there, Happy Endings appears to have a Downton Abbey–esque division of labor. Chill co-showrunner Groff — a fortysomething veteran of Late Night with Conan O’Brien and a proven comedy mechanic on long-running shows like How I Met Your Mother — chats with me on set, asking as many questions as I do, while Caspe, the 33-year-old TV novice (“I had never even seen a writers’ room before this show. It was a huge adjustment”), agonizes over edits (and a Noah’s Ark–sized iced coffee) upstairs. Oftentimes a Jedi/Padawan dynamic at the top of a series can create drama, even on a comedy. But none is evident, particularly because both spend the majority of the interview gushing over the cast. “I don’t know if I’ll ever work with another group like this again,” Groff enthuses. “Any one of these people could be the lead of a show.” Adds Caspe, “All six of them were the only person we wanted for that part. In all cases we had no second choices.” He continues, “This was my first experience with casting, and when I would hear the same lines over and over again I started to feel like, Fuck! This script’s not funny! But then one of these six would come in and do lines that 100 other people had done before them and we would all start laughing.”

Adam Pally: I don’t mean this harshly, but no one wants to live in L.A. But you come here for work.

Casey Wilson: Really? No one is like, can I please raise my kids in L.A.?

Adam Pally: We just had a baby. And we keep thinking, Are we really going to raise this kid in Los Angeles? Is this really happening?

Interviewer: Next thing you know, your kid will be boogie-boarding and then it’s all over.

Adam Pally: If my kid picks up a boogie board, I’ll already be disappointed in him.

Casey Wilson: If your kid picks up a boogie board, you’ll know your wife had sex with Zach Knighton.

Tonight, Happy Endings closes out its own Year of Penny with what might be its strongest episode to date. “Four Weddings and a Funeral (Minus Three Weddings and One Funeral),” written by Josh Bycel and Leila Strachan, is a delirious comic confection, built around an au courant gay ceremony featuring a Skype Table and the reunion of Max’s Material Girl cover band, Mandonna. Lives are altered, relationships questioned, and a napkin is passed off as Brie. But the biggest takeaway, as Happy Endings heads into its summer break (a renewal is not official, but likely), is that, despite most odds, the show has managed to claw its way into the sitcom sweet spot: There is no group of people on television more fun to be around. The pleasure these six get from each other, onscreen and off, is palpable and infectious. It’s the rare sort of synergy that saves bad jokes, elevates good ones, and makes you smile in the rare milliseconds when no one is joking at all.

As I was leaving the set, Adam Pally emerged from a pile of blankets (he was hibernating; it’s a long story) and yelled out to me. “Hey! Grantland guy! An Australian journalist just sent us a bottle of wine as a thank-you. What are you gonna do for us?” How about this: goofy, manic, stumbling, and sweet, Happy Endings has become the most enjoyable comedy on TV.