Half-Life: Blue Shift
At the start of the incident, Harold meets with Rosenberg and Rosenberg's assistants Walter Bennet and Simmons. They formulate a plan of escape which would bring them past not only the Xen wildlife, but the HECU troops as well.
The plan is that they would escape to the prototype teleport in an old sector of Black Mesa, and then use it to escape to the surface. They would then use a Black Mesa SUV to escape from the facility.
Unfortunately, Harold is separated from his allies in an ambush, and hides in an office. Two HECU troops soon find him, though, and fire at him. Fortunately, security guard Barney Calhoun is on the scene, and defeats both soldiers. Harold thanks Barney for his assistance, but is too wounded to help him. He reveals Rosenberg's plan of escape to Barney, and then expires.
Barney relays the news of Harold's demise to Rosenberg and his assistants. Rosenberg and Bennet, in particular, are affected by the news of Harold's death.
Before the incident took place, Harold warned his close friend Rosenberg that the Anti-Mass Spectrometer (designed by Rosenberg) might be pushed beyond safe limits during its test that day. Rosenberg discusses the matter with Keller, but the latter has no power to change the operating levels because the administrator is quite adamant that the Anti-Mass Spectrometer run at the levels he set for it.