Hynes believed he was destined to save the Earth by destroying humanity. When the Tractite Gavril arrived via time tree, he allied himself with the alien. He helped Gavril test a virus which could wipe out all the people on the planet by infecting Rowenna Michaels and Julie Sands.
Jo Grant was able to help them escaped. While being chased by Hynes, they all stumbled into the time tree and were sent back two and a half million years. He found Sam Jones, whom he tricked into helping infect Axeman, one of the local homo habilines. After Hynes ran away, he became more disconnected from reality. He was finally found by Axeman, who killed him. (PROSE: Genocide)