By the time The Two Towers came out, there was no doubt in anybody's mind that Viggo had done a simply amazing job bringing the character of Aragorn to life, and that Peter Jackson and his team had been brilliant in their devotion to the books. There are so many stories of Aragorn wanting to sleep in his costume, of the team pouring over passages in the book to get the scenery just right, of the famous painter Alan Lee actually helping paint the sets because he wanted it to be perfect.
In The Two Towers, Viggo is spellbinding in how he continues to bring Aragorn into reality. This isn't a cardboard hero. Aragorn desperately misses Arwen but knows it was the right thing to do, to let her go with her people. He is attracted to the strong and brave Rohan shieldmaiden, but does not want to lead her on. He has doubts if any of his efforts will make any difference in the end, but helps encourage the troops and stand up against the overwhelmind odds of the Sarumen army.
There are so many little details that add so much to his performance. His flawless linguistic talents, seen in just about every other movie he's been in, shine here as well. His ability to show so much emotion with his eyes, while doing what needs to be done. He doesn't wish for these battles and dark times to be happening, but as they are, he will face them and do his very best to do what is right.
This is truly a hero for the ages, and Viggo nails every emotion, every action. In the scene with the King of Rohan, for example, he wants to have the King make a stand. But even as the potential King of Gondor, he has to respect the King of Rohan's ability to guide his own nation - for better or for worse.
One final note - if you have not yet read the books, READ THEM!! There is SO much more in the books that couldn't be fit into the movies. It gives you a great deal of background and understanding into Aragorn and into WHY Viggo is playing him the way he is.
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