The idea of giving Eleven an older brother wasn't quite clicking. "Nothing was that interesting to us and we said, let’s open this up, let’s go younger," said Matt Duffer. "Let’s make the age group much wider and open it up to women and girls." When Linnea Berthelsen, a Danish actress, auditioned for the role, that's when things began to make sense. The Duffer brothers credited her natural chemistry with Millie Bobby Brown, who plays Eleven, as what got her the part. "You're just looking for something that inspires you or is interesting at all," added Matt Duffer. "It's also super fun to have a discovery and that's really what we were looking at, someone we hadn't seen before." So far, Stranger Things has done a fantastic job of casting incredibly talented new actors.