One of two, as far as I know, nonfiction books by Murakami (I believe he has something relatively new with Seiji Ozawa on music, so maybe three). In 1995, the religious cult Aum Shinrikyo executed five simultaneous attacks on the Tokyo subway system by releasing the chemical weapon sarin gas. 12 people were killed, approximately 50 people were severely injured, and up to 5000 people had at least temporary symptoms. Murakami's interest was in the victims and this book includes his interviews with a variety of survivors and relatives of some non-survivors. The second half of the book includes his interviews with a few Aum members (none of whom were directly involved in, or had prior knowledge of the attack).
Murakami has built a career in writing novels that are often quite critical of Japanese society and its rigid structure of a strict work ethic and a need to conform. This book expands on that - one of the striking things is the consistent trend of the subway victims to desperately try to get to work (or stay on the job in the case of the subway workers) even as they were experiencing symptoms and passing by people who had collapsed (this happened during the morning rush hour). I suspect this was at least partially due to the incomprehension that a chemical weapon attack was actually happening (selected members of the group pierced bags of liquid sarin hidden in newspapers on the trains, so there were no obvious signs that anything was wrong until people began to become ill), but the sense of duty these people felt to their employers is strongly apparent in the interviews. While a few professed anger at Aum members, many others seemed more intent on just putting this in the past and moving on with their lives.
The interviews with the Aum members are also striking. By the time of the interviews, many had left the group (which still exists to this day), but nearly all had positive things to say about it. Murakami suggests that Aum, which required its followers to renounce their past lives and give up everything to become a member, gave these people a means of feeling a part of a group, something that they were lacking, as most of them were outsiders in some way prior to joining. He sees a parallel between Aum and Japanese society in that both required people to give up a good part of their self in order to become a member of that group. Aum members typically weren't willing to give up that part of their self to fit into typical Japanese society, so they turned to Aum as an alternative. While Murakami sees how this ultimately led to the horror of the subway attack, he also sees that for many of the Aum members, they were able to benefit from Aum. All his interviewees had difficulty when he asked them if they would have carried out the attack if asked. Most said no, but they all seemed to realize the ambiguities of the situation they had become involved in.
Like all of Murakami's books, well worth reading.
