In Part One and Part Two I dissected the first two thirds of The Hobbit, and how a screenwriter might break them down into separate movies, with the purpose of trying to see if there is enough source material in a 320-page book to fill 411 minutes of screen time. With the first movie, I think the Blake Snyder "Save the Cat" beatsheet shows that a compelling first movie can be made. The second film, comprising mostly just the company's adventures in Mirkwood seemed a little light on content, and would admittedly need to rely more heavily on invented scenes that are outside the scope of the novel, but brushed in more detail in Tolkien's supplemental works.
That brings us to the third movie and glorious climax to Bilbo Baggins' illustrious career as a burglar. The Hobbit: There and Back Again begins with Thorin's return to the shores of Laketown. Where will it end? Follow along below, and we'll find out.

Seriously? I'm only in the first movie?
The Hobbit: There and Back Again
Opening Image
Laketown. A party is underway.
Setup
The citizens of Laketown are sending Thorin and company to the mountain, and maybe their doom.
Theme Stated
There is dissension between the dwarves and humans, and Thorin is an arrogant guest. Bilbo tries to state that they are better as allies than enemies. He wonders if maybe he is not cut out for adventuring
Catalyst
The Catalyst is what changes. What event turns the hero's life in a new direction he could not have predicted. In this movie, it is the appearance of the grey thrush knocking. The secret door is opened. Bilbo, the burgar, is sent below to burgle.
Debate
The debate here is with the dragon. Bilbo meets Smaug, dialogs with him, and steals the Arkenstone.
Break Into Act 2
Bilbo's break into act two is the act of pissing off Smaug. The dragon rises.
B Story
I believe Jackson could make a promising B story with Bard, who eventually becomes the king of the men of Laketown. There are no human heroes at all in the movie thus far. PJ will make up for it here.
Promise of Premise
This is what we came to see three movies ago. The desolation of Smaug. The ruin of Laketown. Bard's ascension.
Midpoint
This is a high point for the dwarves. They believe they have won, until the arrival of...
Bad Guys Close In
An army of men, intent on splitting the shares of battle. This is not so bad when Dain's company appears except for...
All is Lost
The wood elves showing up with another big army. Now the dwarves are in big trouble. Especially when they hear there may be a 4th army coming. Compounded when...
Dark Night of the Soul
Bilbo decides that he is tired of all of this. He is a very small hobbit in a very big world, and one much too dangerous for him.
Break into Act 3
He gives the Arkenstone away, breaking Thorin's heart.
Finale
The orcs attack. Gandalf returns in the nick of time, with eagles. The batte of five armies goes all sorts of crazy.
Final Image
Thorin dies. Gandalf and Bilbo set off for home. Ian Holm and Elijah Wood say goodbye to the camera for the last time again.
Is there enough in this movie to make a rip-roaring, satisfying end to the three-movie arc? Dammit if it doesn't seem so. Maybe Peter Jackson knows what he's doing. Maybe this film trilogy WILL be the most awesome, accurate, all-encompassing adaptation of all time. I'm convinced. I will watch all three and hope above all hope that PJ finds he still has the magic that turned the first three Tolkien movies into the unqualified masterpieces that they are.

After this, I bet the BBC lets ME be Sherlock next season!
But is there still potential for disaster? Yes, there is. A LOT of people believe the first movie will go all the way through to the Barrel Rider scene. If this is true, then how can there NOT be too much filler? Too much stuff invented for cinema that was not elaborated on by Tolkien. The worst sequences in The Return of the King were the pieces Jackson invented for cinematic juiciness: Pippin lighting the beacon, and Aragorn's army of the dead. If he has to rely on these things to stretch out the second and third movies on account of putting too much of the book into the first, we could be looking at an adaptation more heartbreaking and disappointing than John Carter.
What do you think? Where should the movies break? Can Peter Jackson pull it off? Gather up some pipeweed, grab a chair, and let's chat about it. Find me on Facebook, or follow me @gawainthestout on Twitter. See you there!