Our story turns back to the Ring itself. Frodo has been taken, Samwise is now the Ring Bearer and alone within the realm of Mordor.
This chapter is also all about Team Samwise. He's center stage, taking actions and experiencing the type of luck that only Heroes can count on. The Lord of the Rings doesn't overlook Sam persay... but it rarely features him, instead letting him remain in Frodo's shadow. I'd like to read a Hobbit style telling of The Lord of the Rings, with Samwise as the Bilbo of the story. My insistence of Samwise's role as the true heir of Bilbo is nothing new, I've made comments on it since early in The Fellowship of the Ring. But I feel there's something to be said for analyzing their story arcs and character growth. And now that has me thinking about parallels between Thorin and Frodo... huh.
Through Samwise's bravery, Frodo is recovered, and through some elven blessing, they make it through to continue their quest together.
Jackson lets us see some of Sam's heroics, and thankfully keeps it from going full slapstick. Everything is a bit more to the point without his internal monologue and self-doubt. We don't see him wearing the Ring, but we do see his fear and uncertainty when Frodo demands it back. Actually, Frodo's reaction when he re-dons the Ring may be one of his better moments... it's small and brief, but conveys so much.