You fell into an underground tunnel that appears to be a mineshaft. As you get back your feet you hear an alarm going off, two men stand in a large open chamber with natural light just at the end of the tunnel.

Griggs: "Sheckley!" He raises an SMG at you. "We got Antlions!"

Sheckley: "Griggs you idiot, that's not an Antlion." Sheckley puts his hand on Griggs's gun.