A secret organisation that existed even before the Second Impact. It hid the truth about the Second Impact and the existence of Angels and uses its power to abuse UN and other countries. After the Second Impact, it used UN as a cover, established the Committee of Human Complementation and the secret agency NERV, and built the EVA series.

SEELE's Human Complementation Plan is mapped out according to what was recorded on the "Secret Dead Sea Scrolls". The objective of the plan is to move human up to another stage of evolution. However, with the loss of the Spear of Longinus, and then the rebellion of Ikari Gendou, the commander of the secret agency NERV, it became inevitable that the plan has to be changed at the last stage.

By the way, SEELE means soul in German. All organisations that are related to SEELE, like GEHIRN and NERV, all have their names derived from German. Could it be that these organisations first started in Germany.