Most good stories start with a fundamental list of ingredients: the initial situation, conflict, complication, climax, suspense, denouement, and conclusion. Great writers sometimes shake up the recipe and add some spice.
Initial Situation
Joe Christmas is an orphan with an ambiguous racial ancestry, searching for his place in the world.
As Christmas's story begins, we see how his strange racial origins will haunt him for his entire life, leaving him confused and without an anchor in the world.
Conflict
Christmas is adopted by the McEachern family. Mr. McEachern is so strict that Christmas runs away, drifting from town to town.
In these scenes, Christmas experiences interpersonal conflict with everyone he meets. He loathes McEachern, is disgusted by Mrs. McEachern's kindness, and alienates Bobbie with his violent behavior.
Complication
Christmas starts to break down, fantasizing about killing Joanna Burden and getting increasingly violent with her.
The moodier and more reclusive Christmas becomes, the worse we know it's going to be for his journey of self-discovery.
Climax
Joe Christmas murders Joanna Burden with a razor.
This act is the height of Joe's story, as it forces him to go on the run once again, and we realize that he'll really never find insight into himself now that he's being described as a black man who has murdered a white woman in a racist southern town. He's pretty much screwed, unless…
Suspense
Joe Christmas is on the run. After being captured the first time, he escapes again, and flees to Hightower's house, seeking refuge.
At this point it is unclear whether or not Christmas will survive. It's also ironic that while he murdered Joanna Burden for trying to get him to pray, he ends up looking for shelter in the house of a gatekeeper of religion.
Conclusion
Percy Grimm shoots and castrates Joe Christmas.
Christmas is described as allowing his death to happen, as he lets the crazed Percy Grimm kill him. Unable to reconcile the warring racial factions within him, Christmas decides it's better to die than to have to live as a strange, uncomfortable amalgamation. It almost seems as though there's not yet room in America for a person of mixed race.