Deus Ex is an action RPG with FPS elements known for its pioneering player choice and multiple narrative paths and its thematic use of nanotech body augmentations. It was released in 2000 by Eidos and Ion Storm for Windows and Mac. A PS2 version was released in 2002. You are JC Denton, a United Nations Anti-Terrorist Coalition (UNATCO) anti-terrorism operative in a dystopian world, fighting biotech terrorism.
Since this title is the series' most famous, this tag currently covers both this release and the series.