From the introduction:
The capital of Japan is going through some interesting times. New technologies, a booming economy, the large gathering of the Shomonkai cult, mysterious murders, and people being eaten alive. Oh, and a city-wide lockdown due to a demonic invasion. That’s right, Jumper, shortly after you arrive the city of Tokyo will be put on lockdown by the JSDF, backed and even controlled by Angels, due to an invasion by demons and their lords, the Bels.