The crowd hushes as the rotors begin to spin, their metallic blades carving the air with rhythmic precision. Slowly, at first, the dual rotors gain momentum. Lights glint off the spinning blades.

The crawlspace leads to a bit of a dead-end, a narrow area with a spinning blade in the floor. However, you can see past the spinning blade walls that are portal-able.

Black Mesa East; Ravenholm Travel towards the lambda on the left, get out of the boat and walk around the warehouse. You will enter an airlock that leads to Eli's lab. Follow the other character's ...