Grandfather was the man who came to power after Subject Delta and Eleanor leFt Rapture. During the beginniNg of his reign he reunified much if not all of Rapture and though the city was still chaotic Grandfather would restore order. To assist in this effort Grandfather created the Big Brothers to act as a police force in Rapture making sure the Little Sisters stayed safe and keeping the Splicers under control. Ten years later Grandfather has to deal with the villainous Anarchy, a former Big Brother rebellion against him who in contrasts with Grandfather's plans to bring order to Rapture wants to keep it in chaos. To help deal with Anarchy, Grandfather allows his Big Brothers to test a mind control Plasmid on Splicers that would give them a an overwhelming desire to protect the Little Sisters.