Notice they are wearing leaf-shaped brooches to pin their cloaks. Gifts from Galadriel.

The road distorts as the Dark Riders are about to make themselves known. If you purchase the Toy Biz Frodo action figure, he comes with a stand that illustrates this scene. Quite neat.

Frodo knows danger is drawing near...

Voiceover (Frodo): "Get off the road!"

Frodo yells at Sam, Merry and Pippin who are eating lunch behind him.

The Dark Riders race past the place the Hobbits were just dining.

This is probably when one Dark Rider stops and 'sniffs' for the Hobbits.

Boromir spots something.

Aragorn spins around and yells, "Hide!"

Aragorn grabs Frodo...

...and they both hid under some rocks.

There are two theories on what this scene might be. The first is post Moria when they are still trying to avoid detection by the Moria Orcs. The second could be when they are trying to avoid being spotted by the birds we saw earlier.

The Hobbits hide from the Dark Rider as he sniffs for them.

Frodo stares at the armoured hand of the Dark Rider.

The urge to put on the Ring is probably kicking in about now.

Voiceover (Gandalf): "You must rememberÉ.the Ring is trying to get back to its master."

Cut to the Fellowship outside the gates of Moria. Gandalf has spoken the 'magic words' and the ancient dwarvish design cut into the stone doors is glowing; the doors are beginning to open. Notice the design is exactly as drawn by Tolkien himself.

A shot from inside Moria as the gates open. Frodo stares in curiously.

Voiceover (Gandalf): "It (the Ring) wants to be found."

Amazing shot of Moria that is all you could want - Gandalf's staff makes a tiny light amongst the immense darkness and looming walls and ruinous stairs.

Voiceover (Gandalf): "Let us hope our presence here may go unnoticed."
Just a hint of foreshadowing...heh