Bilbo's Transformation

A great deal has been written about Bilbo's handling of his midlife crisis. 

From a writing perspective, Bilbo is a transformative character par excellence, in part because he transforms without becoming someone else. 

The challenge of the transforming character is the problem of Scrooge (who will naturally come up later). If the character--like the Beast to the Prince--changes too much, the audience might feel somewhat indifferent. After all, replacing Character A with Character B is not much of a transformation. It's just an exchange. 

Bilbo remains Bilbo. But much more than he might have been otherwise. 

From one of my Tolkien posts, I state: 

Bilbo remakes himself; he still values the comforts of the cozy life yet he is willing and able to appreciate the dangers he has experienced:

A pivotal moment echoed by the lines below.

Bilbo Baggins: No! I am glad to have shared in your perils, Thorin. Each and every one of them. It is far more than any Baggins deserves.

Bilbo Baggins: One day I'll remember. Remember everything that happened: the good, the bad, those who survived... and those that did not.

This is the Bilbo who will adopt and raise the near saintly Frodo, who saves not just hobbits but  the entire world. Could (would) Bilbo have done it otherwise?

The remarkable aspect of Tolkien's and Jackson's approach to this change is that redefinitions are epic but the redefinitions themselves are human, ordinary, even small.

"He was my friend," Bilbo says of Thorin in the movie (reflecting the relationship in the book), a small declaration in which the entire Fellowship (and the future of the ring) is contained.