After a preemptive strike against Hiro and Ando in Africa, Arthur Petrelli orders Knox and Flint to hunt down his son Peter and granddaughter Claire. Nathan is stunned to learn his father is alive -- and leading a villainous charge to worldwide destruction. Meanwhile, back at Pinehearst, Sylar has a charged confrontation with Elle. Suresh begins testing his new, combined superpower formula. Later, with the others dead, injured or on the run, Matt attempts to wake Angela.