As Nick moves his way through the organization, he learns of mysterious, psi-based objects that have been the focus of wars over the last century (a cutscene suggests these artifacts are in fact the causes of wars such as World War II). At the same time, he begins noticing strange behavior in Sara, who seems to rotate between friend and foe for no apparent reason. It is eventually discovered that Sara in fact has a twin, who is killed by Sara near the end of the game.