TRUST NO ONE BUT YOURSELF as you adventure into the dark world of espionage amidst the volatile atmosphere of impending war. As a double agent, you must find clever ways to pit enemy factions against each other while eluding pursuers in each of your increasingly dangerous missions.Go to: http://store.steampowered.com/ and download STEAM client
Click “Install Steam” (from the upper right corner)
Install and start application, login with your Account name and Password (create one if you don’t have).
Please follow these instructions to activate a new retail purchase on Steam:
Launch Steam and log into your Steam account.
Click the Games Menu.
Choose Activate a Product on Steam…
Follow the onscreen instructions to complete the process.
After successful code verification go to the “MY GAMES” tab and start downloading.