Japan. Four islands. Four seasons. Four trips. Four current social issues. One book.

That was the plan.

April 2013. Photo-journalist Iwakura and his reporter friend Eri, as she was known to the whole of Japan, would be working together again. Since their collaboration in 2011 had exposed more about the truth surrounding the hijacking of a shinkansen ('bullet train'), they had worked on many articles together, but this would be their first book. The book would be covering some important current social issues such as depopulation, city regeneration, tourism, and work-related suicides.

But fate had another path for them. One where death always seemed to be close at hand.

FOUR is the second book (but first chronologically) in the 'Iwakura Series' continues the adventures of photojournalist 'Rock' Iwakura and journalist Eri Amadera. The book starts in 2013, less than two years after Hijacking Japan was set. Although it contains some spoilers related to that book, it can be read without overly ruining the story and tension if you want to read that one later. Although FOUR is the second in the Iwakura series, it is set before Tokyo 20/20 Vision and helps to explain some of the history and character development that you will have come across if you read that one first. Naturally, it does not matter if you read FOUR before Tokyo 20/20 Vision.