Episode One is the first in a series of games that reveal the aftermath of Half-Life 2 and launch a journey beyond City 17.
Episode Two is the second in a trilogy of new games created by Valve that extends the award-winning and best-selling Half-Life® adventure. As Dr. Gordon Freeman, you were last seen exiting City 17 with Alyx Vance as the Citadel erupted amidst a storm of unknown proportions.