Sean Bean is set to play Zeus.
Who can? Anyone with good acting skills. They already cast Sean Bean to play Zeus, but he's definitely not 10 feet tall.
He plays a protagonist for the whole Lightning Thief book, then it is revealed that he´s a bad guy.
Ares was not cast.
Logan Lerman
Kevin McKidd
Catherine Keener
Ona Grauer plays Artemis in the Lightning Thief, but it has not yet been confirmed if she will continue to play Artemis in the future movies if they are made.
Logan Lerman plays Percy Jackson and Jake Abel plays Luke Castellan in the Lightning Thief .
Well, there might not be any BIG changes to the movie, but there are definitely going to be disappointments. Think about it. There's no one 10 feet tall who can play the gods of Hades, Poseidon, or Zeus. And they already cast Alexandria Daddario to play Annabeth Chase. Annabeth is supposed to be a curly blonde haired girl. Alexandria is a straight brunette. There are definitely going to be some major downsides to the movie. If you've read the book 'Eragon' and watched the movie, you'll notice how bad the movie was. I hope The Lightning Thief Movie isn't going to be another Eragon Movie.
Alexandra Diddario (dadarrio? I don't know...)
Alexandrea plays in the Percy Jackson and the Olympians the lightning thief
I'm not sure they will have a Hermes portrayed in the movie