Whenever aliens attacked, Sumi hid in an abandoned house. She kept wondering what has happened to its owners, so she began to look for anything unusual. When she was about to give up, she found a note under the bedroom. She began to read it. "If you are reading this, then you probably want to contribute, rather than just hide. Igor has taken lead over the city. We heard that he is looking for people capable of fighting so we joined him. You can find him in the City Hall, use the tunnels. Mark and Mary". "I must help them" - said Sumi.