Prisoner David helps Ripley unload the drums filled with the accelerant they use to coat the ducts when they plan to burn the alien and trap it in the Toxic Waste Disposal. When that plan fails and they decide to trap it in the mold, David expresses his fears to Jude who tries to reassure him. He finds the alien on the ceiling and runs from it, and is lucky to have the door close just in time behind him.