Photo: Adult Swim

On his very first night fronting CBS’s Late Late Show last March, James Corden made it clear he had a good idea of the target audience for his 12:35 a.m. program. The British-born host vowed, via song, to entertain all “still awake at this ungodly hour,” including “the stoner who can barely lift her face from off the futon.” Corden is hardly the first post-midnight host to crack wise about the idea that the late-night-TV population contains a plethora of potheads. Some have even catered to this supposed demographic: Back during his NBC days, David Letterman once had an entire rerun episode dubbed with completely new voices. But while late-night talkers no doubt attract more than their fair share of the tired and baked, it’s highly unlikely that old-school broadcast shows are their first choice for televised entertainment. That’s because the most popular destination in late night — for viewers stoned and sober — is actually a once-tiny cult channel that has morphed into a programming powerhouse that now has designs on conquering prime time as well: Adult Swim.

Launched in 2001 as a late-night offshoot of Cartoon Network, Adult Swim has thrived by serving up outrageous, off-color, and just plain bizarre programming, from its first pop-culture breakthrough (Space Ghost Coast to Coast, which predated the network’s official launch) to last fall’s online hit “Too Many Cooks.” Many of its shows seem like they were dreamed up by creators high on … something. But, save for the occasional wink at some viewers’ recreational habits, the Time Warner–owned network has never officially positioned or marketed itself to this cohort. Lingering stereotypes about the channel’s mission statement can probably be traced back to the fact that Adult Swim’s target audience when it launched two decades ago — people ages 18 to 24 who like to stay up late — overlaps with the age group most likely to regularly imbibe.

But over the past ten years, Adult Swim has experienced growth that goes beyond any cliché notions of the late-night audience. The evidence of its success is pretty stunning:

• Last year, Adult Swim averaged more adult viewers under 35 in the 12:35–1:35 a.m. hour — around 575,000 — than any of its time-slot rivals on broadcast or cable. And the race often wasn’t close. CBS’s Late Late Show, then hosted by Craig Ferguson, averaged just 148,000 adults under 35 last year; NBC’s Late Night, hosted for most of 2014 by Seth Meyers, managed 301,000. A few shows Adult Swim aired in the hour did even better: Reruns of Aqua Teen Hunger Force, one of the most regular occupants of the hour, averaged 562,000 viewers in the demo.

• Adult Swim’s power has expanded to the broader demographic of adults 18–49. Its 11:35 p.m–12:35 a.m. fare last year — including a heavy dose of Family Guy and Robot Chicken — drew an average of 1.2 million viewers in that age group. Only Jimmy Fallon’s The Tonight Show (1.7 million) did better in the hour. David Letterman’s last full year as host of Late Show drew about half as many viewers under 50.

• Even when you look at viewers of all ages, cable staples such as Comedy Central’s The Daily Show and The Nightly Show, as well as TBS’s Conan, are no match for Adult Swim shows. Earlier this month, during the week of June 15–19, the 11:35 p.m.–12:35 a.m. programming block on Adult Swim averaged 1.7 million viewers. That’s far more than the same-day audience for either Jon Stewart (1.2 million) or Larry Wilmore (722,000). Conan averaged 596,000 viewers that week.

• Despite only programming from 8 p.m until around 6 a.m., Adult Swim ended the first quarter of 2015 as cable’s No. 1 network among adult viewers under 34 (for the full broadcast day). And during the month of May, Adult Swim was the top cable network in the broader demo of all viewers under 50. What makes these stats impressive is that networks that operate around the clock have a decided advantage over Adult Swim: There are simply more viewers available earlier in the day, when people are, you know, awake. But because Adult Swim is so potent a programming power after midnight — particularly in the sliver of viewers aged 18–24 — its overall numbers stay high.

• The median age of the Adult Swim viewer last year was just 25, making it by far the youngest-skewing non-kiddie network in late night. Among the other big late-night hosts, the only one whose average viewer is under 40 is TBS’s Conan O’Brien (39). Comedy Central’s soon-to-be-extinct duo of Jon Stewart and Stephen Colbert had an audience whose median age was 45 last year, while even the youthful Jimmy Fallon brings in a lot of older folks: The median age of his viewer is 54. (It shouldn’t be hard for Colbert to skew younger: The median age of a Letterman viewer in 2014 was 60.) Adult Swim’s youthful audience composition is even more impressive given the exodus of young millennials away from linear TV.

Adult Swim’s success has come even though it hasn’t had the sort of massive, singular hit — like FX’s The Shield or Comedy Central’s South Park — that catapults a network to the next level of ratings success almost overnight. The quirky, seemingly niche shows in which it specializes would also appear, at least on paper, to appeal to far fewer viewers than the more mainstream comedy of a Seth Meyers or Jon Stewart. But looking back at Adult Swim’s history over the past two decades, it becomes clear that execs at the network — led by founder and day-to-day chief Mike Lazzo — have consistently put the idea of building a channel that’s a destination for viewers over launching specific programs. Sure, there have been plenty of hits over the years, from Robot Chicken to the recent Rick and Morty. But Adult Swim seems to thrive because its viewers know they can trust it to entertain them, to give them something different and interesting (even if every at-bat doesn’t result in a hit). Creators who’ve worked for the channel, including Rick and Morty’s Dan Harmon, have also raved about the creative freedom and level of support the network provides. (It helps that Adult Swim produces shows for a relative pittance compared to most networks; it’s easier to take risks when there’s less on the line.)

Likewise, Adult Swim trusts its viewers to find their shows without the benefit of the multi-million-dollar marketing campaigns so common in TV. Lazzo, in numerous published reports over the years, has said that Adult Swim’s iconic on-air bumpers came about because he decided he’d rather use the $1 million or more usually reserved for network “branding” on developing more original content. Similarly, there was no marketing budget for “Too Many Cooks,” which first debuted at 4 a.m. and became a word-of-mouth hit more than a week after its first broadcast. The network’s willingness to experiment with program lengths — many shows are just 15 minutes in length, while specials such as “Cooks” and The Greatest Event in Television History have no fixed time — also has benefits. For one, it maximizes the number of creative shots it can take with its limited budgets. (Its 2015–16 development roster unveiled in May contains more than 30 different projects.) But shorter runtimes also play to younger viewers’ shrunken attention spans in the age of YouTube and limitless non-linear program choices. It’s a lot easier to graze Adult Swim than traditional networks.

Adult Swim has also had some help from someone who, until recently, had no formal creative association with the network: Seth MacFarlane. In the same way TNT and USA used Law & Order to build their ratings, reruns of MacFarlane’s Family Guy and American Dad! have been massive on Adult Swim. (MacFarlane once even used a Family Guy episode to argue his shows were funnier on Adult Swim.) They’re a big reason the network has made inroads earlier in the evening. But viewers drawn to Adult Swim by reruns of already-popular shows from Fox’s animation lineup (King of the Hill and Bob’s Burgers are also staples) have also stayed for the even more insane Adult Swim originals. The relationship between MacFarlane and Adult Swim came full circle last year when the network joined forces with sister channel TBS to keep Dad! in production after Fox essentially canceled the show. (Originals debut on TBS and then replay on Adult Swim.)

Executives at the network politely declined to be interviewed or comment for this article, perhaps concerned about reinforcing old clichés about their audience. Last year, however, Stuart Snyder, who until last year oversaw Adult Swim as part of his role as president of Turner Broadcasting’s animation and young-adult unit, talked to us about the network’s plans to expand further into prime time — and to grow its audience beyond those core fans already invested in the channel’s late-night offerings. The first step in the network’s bid for prime-time domination came last spring, when it moved up the start of its program day to 8 p.m. By starting earlier in the night, Snyder said, “It gives momentum and enables us to build [audience] throughout the night.”

So far, Adult Swim has programmed the earlier hours with reruns of shows such as King of the Hill, a much more traditional animated show with appeal to audiences of all ages. But in the next year or two, the extra real estate will result in more series like Rick and Morty: half-hour programs, probably produced at a slightly higher budget than many of the network’s past 15-minute shows. Having successfully stolen late night from network talk-show hosts, Adult Swim is now setting its sights on stealing away young viewers from the sitcoms, dramas, and reality shows that now dominate prime time. As Christina Miller, who serves as general manager of Adult Swim and two other Turner animation, told The Wall Street Journal recently, “We want to … create original hits that can be more broad without losing the Adult Swim sensibility.” It’s the sort of ambition that will require Adult Swim to aim high. Pun not intended.