In his commentary on the DVD,
Joss Whedon made specific mention that
Chiwetel Ejiofor,
Nathan Fillion,
Summer Glau and
Sean Maher all performed many of their own stunts. Summer Glau, in reality a trained dancer, used her dancing skills in River's two fights - for the second, the cameraman, who was also a dancer, moved through a gap around the combatants in order to achieve the dynamic camera angles which appear in the movie.
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