After Black Mesa plummeted into the ground 200 years after the incident, it was brought back to life by a group of Blue-Headed men all named "Jamie". Jamie and all his friends now work at the lab, and ironically enough the same exact thing that happened 200 years ago happens again. Even with Gordon Freeman brought back from the dead.
Quite fun. It is a nice way to cure short term depression. I was feeling a little depressed about losing something, but then I played this and I stopped caring. I think the mapping needs to be changed a little more, though.