The Third Brain was a powerful brain originally devised for good, when Gregorio Cortez worked on the project. The goal of the Third Brain was to create artificial intelligence equivalent to the intelligence of the best spies. It was remodeled into the Fifth Brain, and was multiplied to put into robot kids.
Twelve years ago they were part of a research team for the OSS, attempting to create a synthetic intelligence, a compendium of spy knowledge, if you will. Research since destroyed.