It's been a long time since Saki used to fight an army of rival bikers in the darkness, but an unexpected encounter with the family of an old friend draws her into back into the kind of rough scene that could be anathema to her idol activities.

The girls of Franchouchou are going to have a dedicated concert! With a crowd capacity of five hundred! And Kotaro's plan to get them ready is... training in the mountains? Will his braindead idea pay off?