Let’s face it, we all do it. You see a picture online and think, “Ohmygod, that’s [insert name of character here]!” I know I’ve done it. I once found my character, Scott, but didn’t know who the model was (for a long time, I did find it eventually, I think I’ve lost it again, though):
But once you have that image of a character in your mind, it’s pretty difficult to get rid of. In some cases, this works in your favour. In others? Not so much.
In the script I’m writing at the moment, I have cast my characters. I’ve even broadcast to the world who I want to play who! I find this useful; I’m using actor’s appearances to my benefit.
However, in prose, I don’t like to think about who would play them. Scott was an exception – I saw the picture, and gasped out, “That’s Scott!” It was just something that happened (it’s kinda scary how much that guy up there looks like Scott).