what is the theme of the 21st episode?
A group of survivors prepare for an upcoming raid on their camp by the "Others", while the rest prepare to contact a nearby freighter.
Greatest Hits (Lost)
A group of survivors prepare for an upcoming raid on their camp by the "Others", while the rest prepare to contact a nearby freighter. 
what is the greatest hits 'lost'? The 21st episode of the third season of "Lost" and 70th episode of the series. is it a movie or a novel? A TV series. when did it first release? May 16, 2007. who is the producer of these series? Edward Kitsis and Adam Horowitz. where is the first one from? America. where did he complete his studies from? University of Wisconsin–Madison. did he produce anything else apart from the series? He wrote the sequel to the film "Tron". and where is the other producer from? America. what did he start his career as? He was writer and reporter for the "Daily Cardinal" student newspaper.
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Greatest Hits (Lost) [SEP] Introduction
Charlie Pace (played by Dominic Monaghan) recounts the five greatest moments of his life, which are depicted in flashbacks, as he prepares to fulfill Desmond Hume's (Henry Ian Cusick) premonitions of his death.