Cacophony has been defeated and music has returned to Equestria. Thunder Growl and the other members of My Metal Pony are invited to participate in the Equestrian Battle of the Bands, a kingdom-wide competition with a huge grand prize. It is the opportunity of a lifetime.

However, all is not well. Three of the band members are still suffering from their time as a part of Cacophony, suffering from nightmares, panic attacks, and worse. On the very day that they recieve the invitation to compete, one of the band members decides that he just can't take it anymore.

Thunder Growl and his friends must fight their own personal battles before thinking about the Battle.