mischa collins I could actually see as harry, he can do grouchy and has a wizardy sort of voice. Might require a different sort of comedic timing than you see with castiel though. Remember, Harry is cool because he is also a total dork Mischa seems more suited to play the straight cool guy.
Are you kidding?
Seriously, are you?
Misha Collins is probably one of the funniest people on the planet because he does dead pan humor. He's a complete dork. He doesn't act it all the time, but he is one of the few actors I love who would be absolutely perfect for Harry. Not even kidding, go to his Twitter (@mishacollins) and read some of the stuff he puts up. He talks about everything from President Obama needing his help for foreign policy, to Queen Elizabeth wanting to behead him, to having to hide in an underground bunker with only a pony for food. (not seriously, thank God, but it was hilarious the first time I read it).
And then, just to round it off, go look up some videos of him at the Supernatural conventions (just to name a few, Supernatural cons are usually shortened by the name of the con and the city, plus the annual number of the convention -- for instance, JIB-Con Spain 5. JIB stands for one of the episode titles,
Jus In Bello, Asylum 5, All Hell Breaks Loose, AHBL -- actually, I still don't know what that one stands for, but you get the idea.)
He plays the incredibly serious Castiel (and he explains it in this video:
http://www.youtube.com/watch?v=HUPaGD9zlnc) because the mytharc behind Cas is that, his true form makes people's eyes bleed, and the true sound of his voice could make your head explode -- and more recently, he informed everyone in character that his true form is also as big as the Chrysler Building -- ergo, it seemed only right to make Cas' voice sound deep and gravelly.
He's just too short
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