Newsarama has a great interview with Legion producer/showrunner James Tucker. Some of the highlights:
NRAMA: There are many versions of the Legion of Super-Heroes over their 40+ years of existence. How would you describe yours?
JT: Well, I feel blessed to have a property like Legion that has very passionate fans who have endured multiple reboots of the series and still are in love with the idea of the Legion. There are a lot of great eras of Legion, and all of them have things that we cherry-pick from.
Our Legion won't belong to any specific era of the book, but I sort of think it has the lighter tone of the Silver age stories with the intensity of the later stories from that era that Jim Shooter ushered in, along with the funky spirit and energy of the later eras. Although, again, we sampled from almost all of the eras.
NRAMA: Who are the key members of this Legion? Obviously you have 50+ members to consider, so doing them all, all the time is out of the question.
JT: The key members initially will be Brainiac 5, Saturn Girl, Lightning Lad, Bouncing Boy, Timberwolf, Phantom Girl, and to a lesser degree, Triplicate Girl. And Superman!
NRAMA: We did a little poll among the staff for main names in the Legion. Will any of the following be there?
Cosmic Boy Chameleon Princess Projectra Mon-El Ultra Boy Colossal Kid/Giant Boy Invisible Boy Karate Kid Shrinking Violet Shadow Lass
JT: Five won't be in the first season, but the rest will. That's all I'm gonna say.
NRAMA: That said, we know the powers of the various characters of the comic, but what can you say about their personalities?
JT: Lightning Lad is eager, hot-headed and prone to fighting first and thinking later.
Saturn Girl is level-headed and ethereal, composed at all times but also very physical. Glen Murakami always thought of her character as someone who doesn't really understand physical boundaries and is always touching people and knowing their deepest thoughts.
Brainiac 5 in our Legion will be younger than all the other members and yet the smartest one. I have always thought of him as kind of a "Little Man Tate"-type character. A kid who is so smart he's sent to college when he's only 12. For the purposes of the show, we messed with his character a little bit (or a lot, depending on who you ask) by making him very much a descendant of old-school Brainiacs, and therefore he's still basically a robot boy. His deep desire, though, is to be more human, like his team mates. So, in a way, he's somewhat like Pinocchio. I think this version of Brainy is closest to the DnA version in personality combined with the robotic aspects of the character Gear from that series. I was definitely inspired by Oliver Coipel's rendition of him when designing him.
Phantom Girl is a princess who is kind of spoiled, but ultimately very devoted to being in the Legion. She has a somewhat sarcastic attitude to cover the fact that she really gets a kick out of finally being with other kids like herself.
Bouncing Boy is kind of the everyman member of the Legion. He's very down to earth and pragmatic. In a lot of ways he plays Bones to Brainiac 5's McCoy (Star Trek comparison). We play him a little bit for comedy, but when it's time for action he's the first one to lead the charge.
Timberwolf is a loner but longs to be closer to people. His appearance makes him look a bit feral, but his personality is anything but. He's the cool dude who's actually insecure inside.
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