Infiltrator — S.M. Stirling

Both Sarah and John Connor have survived repeated attempts on their lives by advanced Terminator killing machines sent from a grim tomorrow to ensure the total destruction of humankind. Now, hiding out from the U.S. Government in Paraguay, Sarah and her brilliant son have linked up with Dieter von Rossbach -- a former counterterrorism operative and the human model for the original T-800 -- awakening him to the nightmare to come and drawing him into their revolution. Because the Cyberdyne Corporation's plan to launch its dread Skynet program was not destroyed, merely postponed. And the machine masters of the near future have sent a terrifying new breed of enforcer back to the Connors' time: a cyborg so humanlike that detection is virtually impossible; a relentless hybrid killer who understands how her human prey think and feel...and die.