Luna elaborates that showrunner Tony Gilroy, who also co-wrote the screenplay to “Rogue One,” had all the answers to what was once a hint of a character’s larger backstory:
“What does it mean to start a fight when you’re six years old? What makes you miss your childhood that way, that you are part of a movement already? We’re going to see what that line meant, and I was just shocked when I read what Tony [Gilroy] was proposing — which happens to me often with the writing of Tony Gilroy. It’s so complex and unique, but it’s so juicy also.”
It’s exciting that the person who created Cassian has been given the opportunity to revisit this character. In “Rogue One,” there’s something quite haunted about him. He’s hardened and battle torn, quick to judge and slow to trust those not immediately allied with him. Evidently, when a Rebel officer orders him to kill Galen Erso at first opportunity, there’s an implication that he has plenty of blood on his hands. When he references the sacrifices he’s made in his life, he also means the moral compromises he has had to make for the rebellion’s survival, and by extension, his own survival.