Valve, of the series Half-Life and Counter-Strike, announced Half-Life 2: Episode One debuted at #1 on retail PC game charts across Europe, including the dominate markets of Germany, UK and France.

Episode One, released at retail outlets and via Steam on June 1st, is the first in a trilogy of episodes that will conclude by Christmas of 2007.

"After spending six years creating Half-Life 2, we decided to build HL2's successor as a trilogy of episodes," said Gabe Newell, Valve's president and co-founder.
"This has allowed us take greater risks in gameplay, move the technology forward faster, and let people know what happened when the Citadel blew up in 18 months, rather than asking them to wait 6 years."

Half-Life 2: Episode One advances the 15-million unit selling franchise and launches a new, three-part series that leads far beyond City 17. Half-Life 2: Episode One does not require Half-Life 2 to play, and is available via Steam and at retail stores around the world.

In addition to the new single player experience, two multiplayer games and a designers' Commentary Mode are also included. And those who purchase Episode One will have free access via Steam to Half-Life 2: Lost Coast, the interactive technology demo that introduces High Dynamic Range lighting to the Source Engine, Valve's game technology.