Man on Fire
After 10 year old Pita (Dakota Fanning) is kidnapped and supposedly murdered, her bodyguard John Creasy (Denzel Washington) goes on a rampage. He kills most of the people involved with the kidnapping, but then discovers Pita is still alive. He exchanges the kidnapper's brother and himself (as insurance that he won't come back later) for Pita's life. Creasy dies of gunshot wounds he sustained earlier on soon after making the trade.
Thanks, James F!