For fun, I’d rather be in Philly

Four twentysomethings running a dive bar in Philadelphia, all of them friends from high school, is a recipe for a much staler sitcom than “It’s Always Sunny in Philadelphia,” debuting on FX Thursday night.

The show, in fact, is a small-scale gem, its characters refreshingly realized and its topic not aggressively dark, as seems to be de rigueur in TV comedy now, from the lite darkness of the network shows “Arrested Development” and “Desperate Housewives” to dark-dark cable comedies like FX’s upcoming “Starved” (narcissist and his obsessive eating behaviors and similarly afflicted friends; review, Page 3) and Showtime’s upcoming “Weeds” (pot-dealing soccer mom supplying to desolate exurbanites).

In shows like those two, there is a presumption, it seems, that the more twisted and damaged the behavior, the more viewers will identify character truth, and in identifying this buy into the comedy. But then a show like “It’s Always Sunny in Philadelphia” comes along and makes that feel arch and over-thought.

The show has a light touch and, more important, an emotional truth; it’s “Friends” (and every assorted knockoff) if “Friends” (and every assorted knockoff) had ever cared to go beyond the clever clubhouse of the writers room and the glamorized unreality of the sets and casting choices and actually belong to the world at large.

The very simple setup of “Philadelphia”: Mac (Rob McElhenney), Charlie (Charlie Day), Dennis (Glenn Howerton) and Dee (Kaitlin Olson) run Paddy’s Irish Pub in Philadelphia, a no-frills neighborhood bar. They’re all 28, 29, that no man’s land of an age, getting into situations that betray their arrested-adolescent instincts and fluid sense of self-worth.

The show has a nice consistency of tone, from the music (breezy strings with a ‘50s feel, reminding you that there’s a TV canon behind this show despite its slacker-cool milieu) to the way it moves around Philadelphia without any fuss, dropping us on a playground basketball court, at the coffee place, on the front porch of a row house.

Each episode has a title that matters, in its deadpan, “Shouts & Murmurs” presentation -- “The Gang Gets Racist,” “Charlie Wants an Abortion,” “Underage Drinking: A National Concern.” The installments have a loose, easy feel; they’re like extended, almost old-school sketches that comment on airborne social issues with believable twists of goofy plot and payoffs that pay off.

In “The Gang Gets Racist,” Dee enlists a black friend from her acting class to help promote the bar, which exposes a racial divide, which gets the guys wondering at the lack of color in their extended friendships. So Mac and Charlie go to Temple University to look for some black people to befriend, with surprising results. In “Charlie Wants an Abortion,” an old high school fling of Charlie’s re-emerges to claim that her out-of-control 10-year-old is his son; meanwhile, Mac discovers that virulently anti-abortion chicks are hot to trot, and further, that anti-abortion protests are good places to try to score (“Pro choice is pro death!” Mac shouts outside a clinic. “Wow, great rhetoric,” the zealot girl he’s shouting with tells him.)

That episode keeps building -- it builds to the moment when Dennis hits up the same protest outside a Planned Parenthood facility and strikes out on the pro-choice side of the fence. “Look, man, there’s no talent over here,” he complains to Mac on his cellphone, and Mac advises him to hop the fence and try the anti-abortion side, whereupon Dennis is egged from both factions.

In this way, “It’s Always Sunny in Philadelphia” is like a Ben Stiller or Will Ferrell comedy but distilled and more compact. You can see how an episode like “Underage Drinking: A National Concern,” in which contorted logic leads the gang to open up the bar to underage drinkers (“We have a social responsibility to provide a safe haven for these kids to be kids,” Mac argues) could just as easily end up as a bloated 90-minute feature.

But here the idea gets the half-hour treatment, starring four relative unknowns who have among them the subtle choreography of a sketch troupe and the believability of actual people. According to the press notes, show creator McElhenney, in young-Hollywood-actor debt and frustrated with his career, made the pilot called “It’s Always Sunny on TV” and shot it with Howerton and Day for $200 on a hand-held digital camera, then edited it on a home computer.

For FX, this became “It’s Always Sunny in Philadelphia.” If this particular back story of Hollywood penury has become a little boilerplate (“they shot it for $6.50, and ate nothing but ramen for two years ... “) here it’s easy to root for. And believe. And enjoy.

*

‘It’s Always Sunny in Philadelphia’

Where: FX

When: 10:30 p.m. Thursday

Ratings: TV-MA (may be unsuitable for children under the age of 17)

Rob McElhenney...Mac

Glenn Howerton...Dennis

Charlie Day...Charlie

Kaitlin Olson...Sweet Dee

Executive producers Rob McElhenney, Charlie Day, Glenn Howerton, John Fortenberry, Michael Rotenberg, Nick Frenkel. Director John Fortenberry. Creator Rob McElhenney. Writer Charlie Day.