A mostly-intact S² Engine is obtained from the corpse of Shamshel and sent to Germany for further study by the Third Branch's Energy Analysis Unit. After the S² Engine is restored, NERV's Second Branch in Nevada undertakes an experiment to install it into Unit-04, which results in the disappearance of the Eva, related facilities, and everything and everyone else within an 89-kilometer radius, swallowed by a Sea of Dirac. An intact S² Engine is never seen in the show, although it is known to be double-helical in structure, much like DNA. (Regular solenoids are shaped like spirals.)