The Black Mesa Incident refers to a catastrophic event that occurred at the Black Mesa Research Facility, a fictional scientific complex in the video game series Half-Life. The incident began when an experiment involving an alien crystal went wrong, leading to a resonance cascade. This caused interdimensional rifts, allowing hostile alien creatures from the dimension known as Xen to invade the facility. As a result of the incident, the facility was overrun, and the U.S. government sent in military personnel to contain the situation. The protagonist, Gordon Freeman, a theoretical physicist, must navigate the chaos, battling both the alien creatures and military forces while trying to escape the facility.