One day, a black pillar suddenly appeared in the Sea of Japan. It was a gate which led to another world, one through which monsters invaded ours.

Dr. Hayakawa, a man famous for his research of "crust energy" went into that other world with his wife, Marie. Upon their safe return, they wrote a book entitled "Kairetsu no Hi (Day of the Field Row)". After that, they went back though the gate once more, never to return.

Their twin children, Yu and Ai, deciding to seek out their parents, goes to the abandoned subway station where, according to "Day of the Field Row", a train which travels to that other world departs at midnight. On the night of a full moon, the train arrives at 0:13:13. Yu and Ai boards this train followed by a mysterious girl named Risa.