The man from Thief and System Shock has teamed up with Valve

Who knows what to expect from this collaboration Gamasutra has revealed that Doug Church, a man behind the Thief series, System Shock and last, has teamed up with Valve. It seems that Doug is from two weeks to work on a mysterious project, still in the making. Church had recently worked on a title from Electronic Arts and Steven Spielberg Project LMNO, an ambitious action adventure planned for Xbox 360 and PS3, but canceled in 2010.

Source: Gamasutra

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System Shock (wikipedia)