From playful opening credits to uncensored vanity cards at each episode’s end, you can’t take your eyes off of the latest spinoff of The Big Bang Theory, which thankfully and happily is unlike anything that’s come before.

The alternate universes are so wildly inventive and so completely wackadoo that I’ll leave you to discover their pleasures for yourself, but let’s just say that if you’ve ever craved a TV sitcom that features centaurs, lecherous telepaths, or characters who share the digestive process of ruminant animals, you might want to check this one out.

The constant change endemic to “Stuart Fails” means sacrificing some of the comforting sameness of a “Big Bang”-style hangout. But the comic chemistry among the main players provides just enough — and besides, the thrilling potential of a constantly wiped slate is worth the trade.

It’s irreverent and diverting and is destined to make you crack a smile more than once during each under-half-hour episode.

Stuart Fails to Save the Universe is both quite clever and quite irritating, but it fails to save the sitcom because it is rarely laugh-out-loud funny. Not in this reality, anyway.

There’s no curiosity about the universes Stuart is passing through, no sense that he registers the untold billions or trillions of lives he’s saving as people rather than abstractions. Even recurring supporting characters like comic book guys Kyle and Trevor, or jockish bro Gary (Tommy Walker), are treated by Stuart and company as one-dimensional NPCs.

Where Young Sheldon was able to translate the aspect of BBT that people loved most — the mix of social awkwardness, relentlessness, and vulnerability of Sheldon Cooper — into a new context, Stuart Fails to Save the Universe fails to bring over any of the good aspects of The Big Bang Theory into this grim mess.