As a seemingly normal day at work starts, Barney Calhoun visits security headquarters, including a shooting range and a surveillance room where it is possible to see Gordon Freeman again on camera heading towards the HEV Storage Area. Calhoun is then sent to help some scientists with an elevator; along the way, he witnesses many incidents foreshadowing the resonance cascade, such as a pair of scientists vainly trying to fix a supercomputer. He also sees the G-Man passing by in a tram. After repairing the elevator, the resonance cascade occurs; the elevator is jammed, the cable snaps and sends Calhoun and two scientists plummeting down the shaft as chaos breaks out around them. As the elevator collides with the bottom of the elevator shaft, Calhoun falls unconscious.