Blue Shift

You are one of the many security guards at the Black Mesa Research Facility, Barney Calhoun. Everyday you take the Transit System to Sector C, then at the end of the day you take it back. Yawn. Today, however, is not like 'everyday'. As usual, the so-called Scientists need help, as the Sector G Access Lift 'won't work'. After walking all the way there though, you simply press a button and the lift works (stupid scientists)! Not for long though. Suddenly, you see loads of 'aliens' start appearing from nowhere. Then the cables snap...