| Black Mesa Research Facility | |
|---|---|
 Logo of Black Mesa | |
| First appearance | Half-Life |
| Last appearance | Half-Life 2: Episode Two |
| Created by | Valve Software |
| Genre | First-person shooter |
| In-universe information | |
| Type | Laboratory |
| Location | New Mexico, United States |
| Characters | Gordon Freeman, Barney Calhoun, Isaac Kleiner, Eli Vance, Wallace Breen, Arne Magnusson, Rosenberg, Gina Cross, Colette Green, Richard Keller |
The Black Mesa Research Facility (also simply called Black Mesa) is a fictional underground laboratory complex that serves as the primary setting for the video game Half-Life and its expansions, as well as its unofficial remake, Black Mesa. It also features in the wider Half-Life universe, including the Portal series. Located in the New Mexico desert in a decommissioned Cold War missile site, it is the former employer of Half-Life's theoretical physicist protagonist, Gordon Freeman, and a competitor of Aperture Science. While the facility ostensibly conducts military-industrial research, its secret experiments into teleportation have caused it to make contact with the alien world of Xen, and its scientists covertly study its life-forms and materials. In a catastrophic event known as the "Black Mesa Incident", an "anti-mass spectrometer" experiment conducted on Xen matter causes a Resonance Cascade disaster that allows aliens to invade Earth, and is the catalyst for the events of the series.
Half-Life was critically acclaimed for its storytelling and level design. At the time, the integration of narrative in the form of interactive cutscenes and NPCs was considered groundbreaking for a first-person shooter.