Redemption is one of my favourite story themes, whatever the medium. The simple yet complex act of a character realizing they've wronged someone and seeking atonement or forgiveness is both powerful and rare, as it is in real life, I suppose.
Don't get me wrong, I like a tale of bloody minded vengeance as much as the next red-blooded fellow, from Batman to the Count of Monte Cristo (or better still, Inigo Montoya), but in the long run, understanding and forgiveness stand to trump. "When you set out for revenge, first dig two graves," James Bond intones, drawing from a supposed Chinese proverb, and it stands to reason that in seeking to wound, more damage can be done to oneself. In "V for Vendetta", Evey Hammond has the opportunity to seek revenge simply by cutting a rose blossom and handing it to the title character, but she says instead, "Let it grow."
A recent re-watching of "The Lord of the Rings" got me to thinking though; there are a lot of spurned opportunities for redemption or reconciliation in this story. Theoden refuses to call his nephew Eomer back to Helm's Deep. Grima spits on Aragorn's offered hand, even though Aragorn has just saved his life. Denethor, in his madness, would rather be immolated with his son than try to heal him. Saruman refuses to cooperate with the victors after the fall of Isengard, and in the book, he goes on to take over much of the Shire. Even though the themes of friendship, loyalty and goodness continue unabated, few are those who avail themselves of the hands offered.
This appreciation for redemption is probably why one of my favourite scenes is Boromir's defense of the hobbits at the end of "The Fellowship of the Rings". It's almost an afterthought in the book, related by Boromir as he lays dying, confessing his weakness to Aragorn who absolves him and praises his valour. Sean Bean's portrayal in the film is fantastic, his face laden with guilt and shameful anger which he dutiful parcels out to the orcs pursuing the hobbits. The tragedy of the scene is mitigated a bit by the scores of slain uruk's surrounding him when Aragorn finally arrives. (As an aside, I do wish they had followed the book's lead and heaped the weapons of the vanquished on the boat with him before they sent it over the falls, but given the sheer number of fallen, they may have needed a bigger boat.)
Boromir's valiant but ultimately futile effort to save Merry and Pippin is one of the few examples where a character recognizes his wrongdoing and tries to make up for it in any real fashion; in fact, it is so rare it is practically the exception that proves the rule. The fact that the heroes of the tale continue to offer mercy in the face of nearly constant refusal speaks more to their virtues than to their opponents' shortcomings, I think. Still, I wonder if this was an intentional choice by Prof. Tolkien, to reflect the rarity of such transformations in both art and life.