 Fred and Wilma s favorite TV show, Hum Along with Herman, organize a "Barber shop quartet" contest. Fred organizes it with the help of two gravel pit workmates and Barney at the last moment. However, since Barney is unable to sing except in the bathtub, Fred organize the act with a rolling bathtub in order that Barney can sing the right notes. But bringing the bathtub into Bedrock is not such an easy task...