"In the heart of Loki there is the heart of a lost child and around it he’s wrapped in a cloak of hatred and anger and pain and enormous power. But I think it’s much more exciting if I think there’s always a possibility, because then it makes him three-dimensional, it makes him complex, and you hope some people in the audience are fighting for that. It’s part of Thor’s motivation. It’s part of what makes Thor a good character, because Thor is fighting for his brother back. He wants his brother! He appeals to their childhood in this film, he says, “We fought together, played together. Do you remember none of that?” And Loki’s response is, “I remember a shadow.” So I hope that somewhere down the line – I haven’t seen a script for Thor 2 – I hope that somewhere in Thor 2 that’s something that is expanded on. I keep finding myself saying, I can’t remember who said it, but, “The opposite of love is not hate, but indifference” and Loki is not indifferent to Thor. Loki hates Thor, which must mean that underneath that he still loves him."

—  - Tom Hiddleston.