‘It’s Always Sunny in Philadelphia’ is the longest-running US sitcom . What’s its secret to being so good?

Has any series still held it together after 18 years on the air? The Simpsons – the yellow-cheeked poster boy for televisual longevity, now 34 seasons deep into its run – started dipping after just eight, and nosediving soon after. Frasier ran for 11 seasons but began losing its mojo after six or seven. Modern Family; The Big Bang Theory; the list goes on. On Friday, It’s Always Sunny in Philadelphia returned to Netflix UK for its 16th season. The cult TV show is now, season for season, the longest-running live-action American sitcom ever, having surpassed The Adventures of Ozzie and Harriet in 2021. Even more remarkable is this: after nearly two decades, it’s still genuinely, reliably good.

Always Sunny follows five dysfunctional narcissists – twins Dennis and Dee (Glen Howerton and Kaitlin Olson), their non-biological father Frank (Danny DeVito), Charlie (Charlie Day) and Mac (Rob McElhenney) – as they run a dive bar in south Philadelphia. Like many great sitcoms (Parks and Recreation; Seinfeld; The Office US), it took a ropey first year for the series to find its footing. DeVito joined at the start of season two, and the group’s repartee immediately clicked into place; his Frank, a grotesque wheeler-dealer, is a perennial highlight. Sunny’s premise has always been a loose one: often, episodes will see “the gang” throw themselves into an ill-fated scheme in some effort to get rich, enact some kind of revenge, or merely amuse themselves. Examples: Dennis and Dee start smoking crack cocaine in order to claim welfare benefits; Mac and Charlie stage their own deaths; Charlie stages a musical to try and impress the waitress he’s been stalking. The series has always been a satire at heart, with the venal quintet embodying the ugliest sides of the American psyche – bigotry, hubris, avarice and ignorance.

The first episode of the new season, “The Gang Inflates”, is one of the best the series has produced in years. It sees the gang embroiled in a jumble of harebrained schemes circling loosely around the idea of inflation. By this point, Sunny has developed a confident comic shorthand; it takes just seconds from the episode beginning for things to start unravelling. Frank attempts to explain inflation to Mac and Dennis, here playing the part of gullible rubes, and swindles them out of money in the process. Dee, meanwhile, is being evicted from her house thanks to inflated rent prices and has superglued herself to the wall in protest. She keeps phoning the rest of the gang; they keep hanging up after seconds and returning to their spurious economics lesson. Stupidity; greed; misogyny: it’s all there on show, and the episode is barely a minute in.

From here, the episode spirals out into lunacy. Charlie tries to get Frank to invest in cryptocurrency. Dennis tries to start a business renting inflatable furniture. Mac, misunderstanding a metaphor about “getting one’s [financial] nut”, balloons his face into allergic puffiness by devouring a bulk-value tub of nuts. It’s a classic Always Sunny episode, grown from a quintessentially unhinged Sunny premise. The fact that the series is still able to pull episodes like this from the aether is a testament to the rare comedic chemistry of its stars – including McElhenney, Howerton and Day, who created the series together – as well as a number of shrewd ways in which it bucks the norms of television.

Chief among these is the decision, early on, to eschew any ideas of personal growth or character arcs. One of the most common problems to hamper long-running series is the tendency for characters to simply run out of road, narratively speaking. In Frasier, things lost steam once Niles and Daphne resolved their romantic tension. Friends pushed its intra-cast romances to the limit, with Chandler and Monica’s relationship congealing into a staid marriage, and Ross and Rachel’s will-they-won’t-they necessitating all manner of contrived roadblocks to forestall the eventual “yes, they will”.

In Always Sunny, though, none of the characters grow at all. None find love or partners. (Dennis gets married early on, and is divorced one episode later.) While most shows strive to endear their characters to viewers over time, Always Sunny pulls in the opposite direction: the gang only grows more behaviourally abrasive, aesthetically repulsive and otherwise generally unlikeable over the years. The series has also shunned serialisation, in any real or meaningful sense. (Mac coming out as gay in the 2017 episode “Hero or Hate Crime?” is one of the few exceptions to this.) If there was a rulebook for how to make a long-running TV show, Always Sunny has ripped it up, doused it in petrol, and set the shreds alight. And yet, it’s worked.

It should be noted that Always Sunny has benefitted from the sparse production model of contemporary American TV. If it had been made two decades ago, when 22-episode seasons were de rigueur, it’s unlikely Sunny would have survived so long. For example, the six seasons of The Simpsons that are widely regarded as its “Golden Era” yielded 143 episodes – nearly as many as Sunny has mustered in its entire run. But 16 seasons and 170 episodes is not nothing. It’s a tally that puts most British TV to shame.

Longevity in TV can be a curse as often as it is a blessing; rare is the long-running series that does not eventually outlive its welcome. Episodes such as “The Gang Inflates”, however, show that creative decline is not the inevitability some claim it is. For now, at least, Always Sunny is beating the curse. Long may it continue.

‘Always Sunny’ is available to stream on Netflix in the UK