In many ways, this is where it all began. Jerome Kern and Oscar Hammerstein's 1927 musical was the first attempt to use songs to advance a plot. Previously, musical entertainments were a collection of often upbeat random numbers, normally about love and often sung by princes and princesses. But Hammerstein's story - based on the novel of the same name by Edna Ferber - was about real people, black former slaves toiling on the Mississippi delta for a pittance so small it soured the sweet taste of freedom. And there are also white showbiz people who worked the show boat that brought glitz to the segregated south.
Daniel Evans's terrific Sheffield production is the third show in London to follow what might be called the Fanny Brice, Funny Girl template.
Here, it follows the fate of Magnolia, daughter of floating showman Captain Andy Hawks (Malcolm Sinclair). She falls in love with a good- hearted but no-good gambler (Chris Peluso) who drags her down, then leaves her.
After a period of misery, the betrayal allows her stage talent to blossom. Something similar happens to Fanny Brice in Funny Girl and even Carole King in Beautiful. It's a good, reliable story. But it's not much without a brilliant score, and there are few more beautiful than this.
Emmanuel Kojo does the near impossible with Ol' Man River in that, though he doesn't eclipse memories of Paul Robeson - nobody could - he does emerge from Robeson's shadow with the right to claim his own place in the song's history.
As with most of the high points in this production - and there are many - that number begins as a solitary voice. But as Kojo's Joe is joined by his fellow stevedores, or in Can't Help Lovin' Dat Man when Rebecca Trehearn's Minelli-esque Julie is joined by the ensemble, the music swells like a fathom-deep ocean wave.
This might easily be the best sung musical in the West End. And just when the choral power and momentum has reached its peak, Sandra Marvin's Queenie hoists the ecstasy level of this show even higher.
Lez Brotherstern's design, primarily a wall of wooden planks, could be - what's the word - boatier. But driven by Hammerstein's story, which moves at the speed of a rip tide, Evans manages to suggest the grand sweep of lives affected by America's civil-rights struggle without pausing to get all preachy about it. And so brilliant is this example of a genre that melds music and storytelling, it still feels like revolutionary stuff.