Yuji Hongo is an ex-member of the Self‐Defense Force. On December 24, 2017, his wife and daughter go to the observatory of a Tokyo government office building. An explosion occurs at the Tokyo government office building and Yuji Hongo learns the explosion was caused by the international terrorist group IF. They are holding people people hostage including his wife and daughter. To save his wife and daughter, Yuji Hongo sneaks into the government office building.