As the series begins, a number of threats have arisen to menace the empire: from within, rebels (including rogue computer hackers known as "cyberats"), clones and espers have started to fight for their basic human rights, although until their disparate organisations are unified by Owen Deathstalker their efforts are largely ineffective. From without, the empire's current "enemy of humanity" (a title reserved for the greatest danger to the empire) is "Shub" – a of artificial intelligences created by the empire that, upon achieving sentience, went rogue and escaped from imperial control.