What happens, when a group of people start killing other people with a little reason? You would be shocked after listening it but the storyline of the movie Sins Expiation is based on that. There are two different stories in the movie. In the first story, there is a black man, who is telling his story, that how he was a killer and how he killed the people at that time. On the other hand, there is another man, who is killing the people without showing any mercy on them. The people, who come between his missions, he kills them. Why they were killing the people? What were the secrets behind that?