It seems that it was Bai Ling, playing the role of Scavenger. This is from a review which was too long, so I didn't read it all.
Her name is also in the end credits, if anybody wants to sit until 00:01:26.
Fiona's father has been killed in Florida, but she doesn't believe it was a suicide, and she learns that the prime suspect is a local drug kingpin with an army of mercenaries.