John Rain is a freelance assassin.
His specialty makes him a very desirable asset for any organization with homicidal tendencies: he can eliminate his objectives and make it look accidental. He charges a lot for it but he never misses. He does have three questions before taking an assignment, however. Is the target a woman or child, for he will not go against them? Has anyone else been hired for this job, as he does not want to be tricked up by someone else's mistakes? And is the target a principal?
Born in Japan to a Japanese father and a Caucasian American woman around 1952, Rain lived his early years as a Japanese, though he suffered considerably for being a half-breed. Upon the death of this father when he was becoming a teenager, he moved with his mother to America where he learned that the other side can be just a cruel.
During the Vietnam War, his ability to blend into surroundings, move quickly and quietly, and dispatch with considerable skill brought him training few others received. He learned not only how to kill but that he was very good at it.
After the war, a period of restlessness took him several years to resolve but eventually he ended back in Japan where small amounts of plastic surgery made it easier to blend in. And easier to take up a new trade.
As the series begins, Rain is no longer a young man and is starting to tire of his lonely profession. He doens't pine for a family and a normal life per se but just seems disenchanted with what he has. He knows he is very good at this work but he has a very nice nest egg put away and ponders what else he could do. As the series evolves, this loner becomes entwined with two other characters. First is the alluring Delilah, an Israeli agent who most definitely has her own agenda but who falls for Rain as he does her, and Dox, a colleague from his Vietnam days who presents a good old boy attitude while being one of the best snipers in the business. Both of these people play important roles in Rain's life.
And then there is Midori, the jazz musician daughter of one of Rain's victims, who he met, save the life of, fell in love with, created a child with, and then lost. Though she has long since moved with their child to New York to be away from him and his killing, she is still on his mind and still someone that others could and do use as bait.