Summer Glau is an American actress best known for her roles in science fiction and fantasy TV series and movies. Some of her most notable works include: TV Shows:

• Firefly (2002), where she played River Tam, a troubled child prodigy on a renegade spaceship crew.
• Terminator: The Sarah Connor Chronicles (2008–2009), in which she portrayed Cameron Phillips, a reprogrammed Terminator sent to protect John Connor.
• The 4400 (2005–2007) as Tess Doerner.
• Arrow (2013–2014) as Isabel Rochev / Ravager.
• The Unit , Dollhouse , The Big Bang Theory (guest appearance as herself), CSI: Crime Scene Investigation , Cold Case , Hawaii Five-0 , and The Cape.

Movies:

• Serenity (2005), the film continuation of Firefly , where she reprised her role as River Tam.
• Knights of Badassdom (2013).
• Superman/Batman: Apocalypse (voice role).
• Mammoth (horror comedy).
• Deadly Honeymoon (2010).
• The Legend of Hell's Gate: An American Conspiracy (2011).

Summer Glau is recognized for her ballet background, which she has incorporated into some of her roles, notably in Terminator: The Sarah Connor Chronicles where her character performs ballet in certain scenes