To me at least, the Orcs are easily the most likeable race on Middle-Earth. Their dialogue is snappy, punchy and to the point, and they have a lot of humor. When the Orcs complain about having to move through sunlight, their leader urges them with, "oh, don't worry, you'll move fast enough with me behind you." There's another sequence where one of them asks if they should stop to rest while in the territory of the Riders of Rohan, and one of them says, "Oh, of course! Then let's invite those cursed horse-boys to a picnic afterward, while we're at it?"
After all the rhymed poetry and poncy speeches...someone actually used sarcasm in "Lord of the Rings!" It was such a breath of fresh air. Maybe the reason I respond so well to the Orcs is because they sound so American. It's interesting how in Hollywood, an English accent adds to your villainy, whereas Brits make their evil forces sound and talk like Yanks.
Anyway, it's hard not to find amusing a song like "Where there's a whip, there's a way."
The Orcs are tough, skinny and capable of sudden, stabby violence for very little reason. They remind me a little of the Nazi villains from "Inglorious Basterds," who were werewolves in human form.
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Incidentally, speaking of Rohan, you know who Peter Jackson originally wanted for Eowyn? Allison Doody, best known as the Nazi double-agent from Indiana Jones and the Last Crusade. If you were to ask me what her nationality is, the list would be very, very, very long before it gets anywhere near Irish.
I don't know the circumstances, but shoot...if you look like that, and you can't get a part as a Scandinavian warrior princess, it's time to give up acting forever.
The one and only thing that I think Peter Jackson's otherwise extraordinary film version did wrong was that it explicitly made a character as grandiose and terrible as Saruman a mere puppet of Sauron. Saruman and Isengard was more like a very dangerous third factor at play, a second deadly enemy that wanted the power of the Ring for himself, who, perhaps because the characters actually interacted with him, was actually a more dangerous and interesting figure than even the otherwise dull Big Bad Sauron himself. Saruman was the closest these movies got to a "Doctor Doom."
As a consequence, some scenes just don't make sense. For instance, in the book version of Fellowship, when Saruman offers to use the One Ring together with Gandalf, that "together we can be the Lords of the Ring," Gandalf rebuffs him by saying "there can be only one Lord of the Rings, and he would not share power" (referring to the innate evil, jealousy and corruption of the Ring that makes it impossible for more than one to possess it).