Books to Movies: Keeping Characters Together in The Two Towers, Good and Bad

Since audiences invest in certain characters, keeping them together visually  makes sense. 

In the book, Eowyn does not go to Helm's Deep. In fact, the purpose for Helm's Deep is somewhat different in the book than in the movie. Theoden and his riders do retreat there--and women, children, and the elderly as well as goods are being safeguarded there--but only because Helm's Deep is one of many holdings. It is rather like British civilians retreating to the underground even though London wasn't exactly safe (people stayed in London anyway). 

However, it makes sense to bring together the main characters in this particular plot thread, so Legolas, Theoden, Aragorn, Gimli, Eowyn and the Rohan ride together. Unlike in the book, Eomer is absent, which makes for a great final scene in the film. In the book, Gandalf fetches a new character to ride to the rescue--but in a movie, again, the character who has already earned viewer investment is a better choice for a pay-off.

I think wanting to keep characters together--and in mind--is why the elves show up at Helm's Deep. And it makes for a great visual. 

And it makes me wince every time. 

Tolkien is extremely exact about distances and supply chains. There's a reason the Fellowship brings along Bill, and there's a reason Bill is sent away. Aragorn and others are constantly making decisions about goods versus weight versus travel time. There is a VERY good reason why Boromir was able to reach Rivendell without being pursued but 9 people setting out from Rivendell have to be more cautious. And an equally good reason why moving armies from, say, Rohan to Gondor is time-consuming and impossible to completely disguise. (Theoden's troops take a "back roads" approach to Gondor but once they reach a certain point, their presence is a known variable.) 

No matter how stealthy they were, I simply don't buy the idea that hundreds of elves from anywhere could just show up in Helm's Deep without the enemy being aware or, for that matter, Theoden's own scouts. 

The one reason I kind of let it pass is because it references a point not raised in the film or directly in the book (but brought up elsewhere). There were three fronts during the war, including Lothlorien. 

Of course, in reality, the elves should have stayed in Lothlorien to cover that "front." 

Oh, well. Visuals won over reality.