Maka911,893,159 Locked 04 Sep 2008
This is the achievement for beating the game (on any difficulty)
Search "Splinter Cell: Double Agent Next Gen Walkthroughs" to get gameplay for every level, and how to get 100% on hard.
*SPOILERS*
After you beat the Kinshasa mission, there will be a 4th headquarters mission, complete it, and get the achievement.