Finally getting back from the space war with the Meterx the Sonic gang look forward to a long vaction on their home planet but what they come back to is nothing of the sort. They meet a girl named Amy who is willing to help them learn how to survive the war with the undead but how long will they last in this new world when they have to go around killing people they once knew?

Amy Rose used to be normal...but she doesn't remember that life. The moment she awakes is the moment that a new life starts for her. A life that she wants so badly to be as normal as the first. But little does she know that she has a purpose to fulfill: one that will make her choose between the boy she loves and the boy she once knew.