The Pan European Game Information website has a listing for Shadow Complex Remastered, indicating that a PC edition of Shadow Complex is on the way, and will carry a PEGI-16 rating due to "realistic looking violence" (thanks Destructoid). That's all there is for now, so there's no sign of when to expect a release of revamp of Chair Entertainment's platformer. Since the game was released in 2009, here's a refresher from Wikipedia:

The game follows Jason Flemming and his new girlfriend Claire, who opts to explore some caverns the two stumble across. When she does not respond to his calls, Jason follows her. He finds a massive underground complex with soldiers and high-end technology. Jason must rescue Claire and discover the plot behind the faction operating the complex.