A paddle wheeler cruises up the Mississippi, delivering mail and hosting an occasional concert. A scene straight out of the nineteenth century? Not quite. This Mississippi is a toxic brown river. And the paddle wheeler is run by the River Rats, a troop of orphans who survived the Flash, a nuclear holocaust. What were once huge cities are now plague-ridden ruins haunted by gangs of savage children. And the concerts the Rats play are post-apocalyptic rock and roll--a music as rough and ragged as the musicians who perform it.

When the Rats rescue a stranger from the river, all the troubles of the old world suddenly threaten to end their travels forever.