Summer Glau

 Her first TV role was a guest appearance as a ballerina on a 2002 episode of the television show Angel. There she caught the eye of director Joss Whedon, who then was cast in his critically acclaimed , but brief-lived TV series Firefly as River Tam, a role she reprised for the feature film sequel to the show Serenity. Glau was previously a candidate for the part of a Power Ranger (White Wild Force Ranger Alyssa Erile) in Power Rangers Wild Force but was defeated by actress Jessica Rey before meeting Whedon.Glau was in the episode "Love Conquer Al" of the TV series Cold Case. The actress had a small role in the film Sleepover in which she played high school senior Shelly. She was also in the CSI: Crime Scene Investigation episode "What's Eating Gilbert Grissom? " as well as season two of The Unit as Crystal Burns (the girlfriend of Jeremy Erhart). Glau played Tess Doerner (a paranoid, schizophrenic returningee) in the second season of The 4400. From season three, she was an ongoing character. Glau was also in Mammoth, a horror-comedy. Glau appeared in The Initiation of Sarah, an ABC Family TV film. Glau played Cameron Phillips as a Terminator-infiltration team sent back to Skynet to guard John Connor (and Sarah Connor). The series' seventh episode, "The Demon Hand", featured scenes in which Glau (as Cameron) dances ballet. Glau also played Allison Young (Cameron’s human doppelganger in episodes of the second season, "Allison of Palmdale" and"Born to run". Glau was also the lead character on an CBS episode in 2009 of the Big Bang Theory's comedy.