The setup for the Adult Swim series “Smiling Friends,” available on Max, sounds like the premise of a cheery, do-unto-others children’s show: Charlie and Pim (voiced by Zach Hadel and Michael Cusack, the show’s creators) and their kooky pals work at Smiling Friends Inc., where their job is to make clients smile.

But there is nary a shred of cutesy wholesomeness here — instead, there is cursing, bloodshed, absurdity, silliness. The show is so fast and feral it feels like its own highlight reel.

Each 12-minute installment takes us on another deranged misadventure, to odd enclaves and foreign planets, to find lost loves, influence political elections, revamp video-game franchises. “Smiling Friends” has an omnivorous sensibility, and its punchlines can be surreal and warped or grounded and tenderly specific, all part of its grand ethnography of weird little freaks. It also varies its animation style, with Charlie and Pim looking mostly unchanged but guest characters depicted in a range of formats: live action, grotesque illustration, rotoscoped realism.

If some of this character design conjures fond associations with “Tom Goes to the Mayor” or “Beavis and Butt-Head,” well, that’s how you know you are in the right place. “Smiling” is more acrid than “Aqua Teen Hunger Force” and plays by different rules than “It’s Always Sunny in Philadelphia,” but it has a similar naughtiness.

The show first aired as a backdoor pilot in 2020, was ordered to series in 2021, debuted in 2022 and is about to finish its second season on Sunday at midnight on Adult Swim. (It was recently renewed for a third season.) Part of the appeal here is the show’s wide curiosity and unpredictable rhythm; its grab-bagginess recreates the lure of a blind-box toy. There’s also a snacky quality to “Smiling,” thanks to the peppy vulgarity that is basically Adult Swim’s Doritos powder.

Its episodic nature and short running times help, too — though as with any modern show that wants to be loved, Easter eggs and deep-cut callbacks abound.