'We're limited in how far into the future we can predict human attitudes to robots. I like to think of this as the intelligence horizon... Hopefully, beyond this horizon, intelligent robots may be accepted as having at least some rights.'The future for Anastasia and Robert is balanced on a knife-edge. They are key developers of scanning technology used to copy the structure of the human brain and load it into intelligent robots. Their malevolent employer, Augustin, plans to kill them if they try to leave, but also when they outlive their usefulness. They also come under threat from an organisation intent on the elimination of all advanced robots. Meanwhile, two intelligent robots, Rob and Sam-renamed-Penny, have been sent to Mars to help Augustin achieve his all-consuming dream. Can they fend-off attacks by trans-planetary bandits, and use all of their cunning to outwit Augustin?