A dark experiment facility within H.Q., illuminated solely by red light. EVA-00, a cross-shaped stop signal plug having been driven into her
SE <<(OFF) Sounds of glass falling onto the floor and pieces being broken as they are walked upon>>
Ritsuko (OFF):“——— How was Rei?”
Reichu: Crosses are a rather versatile Pointless Religious Symbol™, aren't they?
Keisuke-kun: Just what the hell is the stop signal plug for? Can we assume that if the entry hole isn't constantly filled it will close up like a wound? Regenerate? Has this ever even been speculated on?
Reichu: Tying back to the extensive entry plug comments from the previous episode… I'm pretty sure that there has to be some kind of internal cyborg-ish implant to receive the entry plug, an artificial cavity of sorts, and that they don't just stick it straight into the Eva's raw thoracic cavity.
Sharp-kun: Another possibility is that it is a sure-fire way to prevent the Eva from moving. As a living being, it's still possible for an Eva to move with no plug (as we'll see in episode #05); the stop signal plug perhaps negates that possibility completely. Evas are unpredictable, and they perhaps don't want to take the risk of activation.
Reichu: Indeed; "stop signal plug" implies that it serves a… well… a stopper in the nervous system, to prevent the gap in the Eva's spinal cord from being bridged by the Eva herself. Granted, there do seem to be ways around this (as Shogouki demonstrated in the last episode), but no system is perfect.
