It’s easy to get the feeling, after three surreal, increasingly confounding Pirates of the Caribbean swashbucklers and now Rango, an animated Western that plays like Fear and Loathing in the Mojave, that Gore Verbinski and Johnny Depp can’t resist a bizarre flight of fancy.

It’s more a gift than a curse. Those little indulgences – the scenes that don’t quite fit in but often contain moments of pure, unfiltered imagination – confirm them as artists in an upper echelon of Hollywood’s elite, where playing it safe isn’t paramount. They follow their muse, conventional wisdom be damned.

Rango is a movie alive with such moments. The story itself may be slight, but it’s so richly detailed in the telling, so fearlessly inventive, that complaint would seem simply gratuitous.

Especially in the early going, Rango’s travels suggest a road to nowhere-in-particular, an excuse for Depp to chew the scenery, showing off his facility with dazzling wordplay. Verbinski responds in kind. Liberated from the constraints of live action, he’s free to create full-scale lunacy.

Who is Rango? It’s a question he asks himself often. He’s a domesticated chameleon, separated from his human family, who fancies himself a dramatist. (He’s got one-acts, musical numbers, the works.) But he’s in search of a larger identity. When he arrives in Dirt, the kind of desert town Clint Eastwood once subdued with a narrowed eye, it is Rango’s chance to borrow Eastwod’s persona: The Lizard with No Name.

Bad move. Desperate with thirst and living under the thumb of their enigmatic tortoise mayor (Ned Beatty), the town’s creatures are initially thrilled by Rango’s fanciful tales of Wild West gunslinging. Maybe he can protect them from the mysterious thieves making off with their water.

It’s only a matter of time before Rango is exposed. He’s crafty, but clearly no gunslinger; for him, Clint’s chilling squint doesn’t chill. Yet what happens in his quest for identity, as well as for the heart of a lovelorn lizard named Beans (Isla Fisher), is far less important than how.

The animation is remarkable; Rango’s wonderfully expressive facial quirks speak almost as many volumes as he does. That’s saying a lot for a movie that relies as much on dialogue – so sophisticated that kids might struggle to keep up – as on exhilarating chases. The pacing is uneven, an inevitable consequence of Verbinski’s style. But when he’s on – and Depp is always on – the results are as refreshing as a cooling oasis.