The story revolves around a humanoid genetically modified dog named after Gene Hackman, in the distant future.
Most of the human race has been wiped out, and the few thousand survivors are waiting in suspended animation until the world is habitable again.
At the beginning of the series, Gene the Hackman is the leader of his pack, patrolling Antarctica (which they call "Anarchticy", the name having been corrupted over the centuries).
The urgings stop, something which has never happened before, and so the pack debate whether to return home to report their discovery or continue their patrol (which has already lasted for an unprecedented length of time).
But when Gene's injuries are rapidly healed with advanced medical technology he hasn't seen before, he accepts the possibility that there might be more to the human than meets the eye.
The outpost is attacked by overwhelming numbers of Them, and despite the advanced weaponry available there, Gene is only saved by the timely arrival of another pack.
But many of them have been incapacitated by parasites, "ticks", gruesome bulbous creatures covered with teeth which attach themselves to the giant insects' bodies.
Shortly after recovering from this attack, Gene begins to hear the urgings again, for the first time since discovering the land bridge.
The adults accept Gene, recognising that his combat abilities will be useful in defending the farm against Them, who have recently been attacking with greater frequency and ferocity than before.
He is told that the meat is being grown artificially in a large warehouse, but it is out of bounds and he is strictly forbidden to enter it.
Rex's pet, Paul Numan, tells Gene that three years ago he was in suspended animation on a space station in orbit around the Earth.
He was awoken and sent down to Sydney to investigate some unexplained electrical activity, which turned out to be the result of Rex having discovered how to make the old machines work again.
Numan realises it is because they can detect the scent of Leezee's tick parasite, which is deadly to Them, and they want to destroy it.
Gene only survives because of the intervention of Clara Bow, and the pack allow him to escape, realising that by removing the tick from the Wild Kingdom he may have saved them all from destruction.
Together they discover a base run by robots, where an elderly and insane human general has awoken from suspended animation.
A series of flashbacks throughout the story show the general as a young captain in New Mexico, six years before the last human survivors entered suspended animation.
Clara Bow is held as a hostage, along with some other aux captives whose DNA is not pure enough for the general's purposes.
Aux Drift is abandoned, and the miners take Gene's pack back home to their city, which they call the Kingdom.
During Gene's mission, his pack encounters Numan, who has returned to Earth to investigate whether the Masters' new plan to defeat Them is working.
After the king has been killed, Numan reveals that the Masters took the tick parasite from Leezee Sower and used it to create a biological weapon to infect and destroy Them.
Numan takes Gene (and the only two surviving members of his pack) back to the Masters' space station in orbit.
Gene and Sower escape into an abandoned part of the space station, where they encounter Pause, a renegade aux who has turned against the Masters.
The giant tick, controlling Sower's voice, demands the codes so that its species won't be destroyed.
Gene's shuttle crash lands in Patagonia, pursued by a squad of auxes led by Canis and Numan.
Meanwhile, Pause has requested a nuclear strike by imitating Canis's voice in a radio message to the orbiting satellite.
Meanwhile Us, now led by Numan, are ambushed by a new humanoid form of Them, which have also evolved at a highly accelerated rate in an arms race with the ticks.