Debuting in 2001, Adult Swim made itself known right from its live-action intro: “All kids out of the pool!” The late-night block of Cartoon Network shows catered to adults seeking something edgier, ...

In September 2001—that is, 23 years ago somehow—Cartoon Network launched Adult Swim, a late-night programming block for the kind of people who would check out a kid’s TV channel just to see what it ...