Millie Bobby Brown plays Eleven, a young girl who runs into Mike, Lucas, and Dustin while they're searching for Will. She has tremendous powers and can help lead them to Will. But Eleven has led a horrific life in a nearby lab, being experimented on by Dr. Brenner (Matthew Modine), who she considers her father.
Fun facts: Brown, 12, was born in Spain to British parents. They moved to Orlando when Brown was seven years old, and she began taking acting workshops. That's where an acting scout discovered her and convinced her parents that she would do very well in Hollywood. So, the family soon moved to LA.
Biggest credits so far: Within three months of moving to LA, Brown landed the role of young Alice on ABC's "Once Upon a Time in Wonderland." She then landed a lead role in BBC America drama series, "Intruders." She has also appeared on "NCIS," "Modern Family," and "Grey's Anatomy."
What's next: The second season of "Stranger Things" (not confirmed).