Aqua Teen Hunger Force (tv program)

When he takes command of CBS' "Late Show" next year, Stephen Colbert will have to battle the two Jimmys, Fallon and Kimmel. But he'll also square off against a robot chicken, a mad scientist and a talking hamburger.

From the humblest of beginnings 13 years ago — one early offering was made with microphones purchased at Radio Shack — Adult Swim, Cartoon Network's nighttime block, has a powerful hold on one of the most highly sought-after populations around: young men.

Adult Swim's mostly animated shows — among them hits such as "Robot Chicken," "Aqua Teen Hunger Force" spinoffs and the new "Rick and Morty" — rely...