The First Rebellion happened in a night. It's been a year since the start of the Second Rebellion.
It's been a year since Scootaloo saw her dearest friend leave to join the war. Now old enough herself, Scootaloo volunteers for the Equestrian Army. It's her last hope of finding her friend before the war takes a turn for the worse. The Army can help her outrun death, but she'll soon discover that nothing can prepare her for the pain.
Meanwhile, the Enemy's numbers are growing. Hypnotic Note is one of the best fighters they have. However, jealousy leads to treachery, and Hypnotic finds himself cast out in the wilderness, betrayed by one of his own. Things change when he discovers a secret place, hidden by his species.
The key to ridding the Enemy lies within one pony. The pony who started it all. The pony who is supposed to end it. Who is it?