Cats (1982) by Andrew Lloyd Webber has been in steady production around the world for more than 35 years. You see why in the vibrant show at the Forrest Theatre — through Sunday, June 30 — in which brashly clad cats often prowl through the audience.

Based on T.S. Eliot’s Old Possum’s Book of Practical Cats, it tells the story of the Jellicle cat tribe who gather one night a year for the “Jellicle choice,” where old Deuteronomy (Brandon Michael Nase) decides which cat will ascend to Heaviside Layer, land of eternal catnip and reincarnation.

Keri René Fuller plays Grizabella, the glamorous party girl grown old, and sings the show’s smash hit, “Memory”; director Trevor Nunn wrote the lyrics, based on an Eliot poem. Enormously affecting, Fuller captures Grizabella’s character, a dying cat who summons the strength for a full-throated ending.

Fuller earns the night’s biggest ovation. But “Memory” is the only song of note and is repeatedly reprised. Other songs are more recitative than melodic, always taken over by company ensemble. And the story? What story? Cats is a cat contest in which capering, sparkling felines vie for the honor of Heaviside.

It thus is a musical of contrasting dance spectacles. Andy Blankenbuehler follows the lead of original choreographer Gillian Lynne, infusing the show with an eclectic mix of motifs. As Victoria, Caitlin Bond’s ballet in solo performance is stunning. As Fuller is the unifying force in song, so she is in dance, continually miming cat movements.

Tion Gaston, another balletic performer, electrifies as lead dancer in the ensemble number “Magical Mister Mistoffelees.” Other dance forms slide in and out of the show, capricious as roaming cats. Emily Jeanne Phillips tap dances with gusto as she plays Jennyanydots (“Old Gumby Cat”), the first to vie for Deuteronomy’s favor. Later, Tony d’Alelio and Rose Iannaccone shine as Mungojerrie and Rumpleteazer with their acrobatic duet.

The dazzle never stops, and the show is immersive, with cats streaming through the aisles. Set designer John Napier’s junk-filled alleyway is arresting (he also does the colorful costume design), while the light design of Natasha Katz, a six-time Tony winner, is super-dramatic.

Cats is arguably the first of the globe-trotting “megamusicals,” a genre in which grand spectacle upstages story. Commercially ambitious, it has also been called “McTheater” by detractors, cheesy flash with no ideas. But there are no ideas in T.S. Eliot’s book, either, just fun verse for children. The show is jubilantly childlike, more playful than trivial, living joyfully and fearfully in the moment just like alley cats. For sure, it is not the only way to do musical theater. But it is a fun-loving contribution to a genre that continually reinvents itself.

Theater

Cats

Through June 30 at the Forrest Theatre, 1114 Walnut St. Tickets: $62-$122. Information: 800-447-7400, kimmelcenter.org.