Garland of Thumbs
Read the suttas: MN 86. Part of the story of Angulimalla, "Garland of Thumbs"
This is not about technical details and the story is roughly the same presented by any translator.
Another of the stories that are going on in the background of the suttas.
This is important primarily for the way in which one can arrive at the conclusion that this is a true story. In this case what happens is that perhaps one story of Angulimalla will appear in the Majjhima, another in another collection, a story or two occur in the Jātakas and so forth. In this way we get a kind of triangulimallation on the details.
Notice how King Pasinadi knows Angulimalla's parents. This isn't necessarily because King Pasinadi knows everyone in his kingdom, but is in fact because Angulimalla is High Born. His venture into banditry comes as a religious quest! He was told by a teacher that he would only come to enlightenment after having killed 1000 people. At the point we meet him in this story he has killed 999 and the next person he will kill, if the Buddha does not interfere, is his mother. The Buddha sees this and understanding that if Angulimalla goes this far there will be no hope of recovery for him, he exercises compassion and saves him from a bad end. So we see that Angulimalla's teacher had some vision, for counting Angulimalla's "self" as the thousandth person he kills off, his enlightenment comes right as predicted.
The birth story(s) tell of lifetimes Gotama and Angulimalla have interacted in similar ways.
Another thing that rings true is the "synchronicity" in the saving of Angulimalla and the Visit to the Buddha by King Pasanadi on his way to capture him. This sort of thing happens to those who meditate all the time ... rather this sort of thing happens all the time, and by meditating one sees it ... one is allowed a look at the Great Story Teller at work, as it were.
Another interesting thing to note about this sutta is how powerful the Buddha must have been seen as being by the rulers of the time for him to have just been able to say that the man was reformed and by that to exempt him from any legal punishment. The same thing points to how strong must have been the belief at the time in the reformability of man ... that even one who had murdered 999 individuals could genuinely see the error of his ways and take compensatory measures.
Again considering the same facts, we see the nature of kamma and how even horrendously bad repercussions can be escaped by taking the proper course of action.