Junko Aoki has the gift of 
pyrokinesis: she can set anything on fire with her energy. When she retreats to an abandoned factory to 
displace some of her energy into a huge pool of water there she 
inadvertently witnesses a murder.
The 
Asaba gang has kidnapped a woman and killed her date; they are trying to throw his body into the pool of water so that it won't be detected.
Junko is so incensed at what she sees that she kills three of the gang members by burning them, and as the leader escapes she promises herself that she will seek to 
destroy him as well.
A parallel part of the story tells of 
Chikako Ishizu, the only woman in the Tokyo Metropolitan Police Department, who seeks the person who is setting these fires as well as burning criminals.
A third strand tells of the Guardians, a special group which made me think of the Mob in a way: they have taken it upon themselves to "deliver justice" and formed a band of members with special abilities who also try to do away with criminals. The Guardians woo 
Junko into their midst, luring her with gifts and the promise of love from one of its members.
There are several fascinating aspects to this story:
- the whole idea of pyrokinesis (and other abilities such as telekinesis)
 - the loneliness of those who are set apart by their gifts or hidden talents
 - the way families are effected by those with such gifts
 - the question of justice
 
When we discover that the crossfire is between the victim and the criminal, between the law and those who have taken it upon themselves to deliver justice, we're faced with two critical questions: 
Does anyone have the right to kill another? 
Is there ever a right reason to take a life?
I found this book profound on many levels, not only as a mystery/thriller, but also a treatise on ethics. It was excellent.