Summer Glau was born Summer Lyn Glau on July 24, 1981 in San Antonio, Texas. Glau is a prima ballerina who got her acting start in television commercials and as the ballerina in an episode of the vampire show, Angel
. She has since been cast in another Joss Whedon series, Firefly, and its ensuing film, Serenity. Glau has also appeared in other television shows like Cold Case
, The Unit
and The 4400
River Tam, played by Summer Glau on Firefly, is the gifted but tormented younger sister of Dr. Simon Tam. She endured years of Alliance experiments until Simon rescued her and brought her along on the Serenity. She possesses psychic capabilities and the ability to read most minds, as well as great skill with weapons and the martial arts.
(Photo courtesy of FOX)