Predator's Gold

Part One

Tom and Hester meet adventurer and author Nimrod Pennyroyal aboard Airhaven, who persuades them to take him as a passenger. They are soon pursued by airships of the Green Storm, a fanatical splinter group of the Anti-Traction League, who want the Jenny Haniver as they believe it was stolen from their deceased leader and friend to Tom and Hester, Anna Fang. Despite evading the airships, the Jenny Haniver is damaged and drifts helplessly over the Ice Wastes. They are rescued by Anchorage: once a thriving Traction City that relied primarily upon trade, but was devastated by an excavated biological weapon that killed many of the inhabitants. The survivors have set a course for North America, which is believed to be a radioactive wasteland since the Sixty Minute War. The city is ruled by the young Margravine Freya Rasmussen, who treats all three of them as honoured guests. Tom and Hester rebuild the Jenny Haniver. Hester is jealous of Tom's growing closeness to Freya, and disturbed by the sightings of "ghosts" in the city. Eventually she sees Tom kissing Freya, and flies away from the city in the Jenny Haniver. Thereafter Hester sells Anchorage's course to Piotr Masgard, the leader of the "Huntsmen" of the Traction City of Arkangel, who intends to capture the city through an airship invasion; but insists that when Arkangel eats Anchorage, Tom will be returned to her. As she returns to the Jenny Haniver, however, she is drugged and kidnapped by a Green Storm informant.

Part Two

Hester is taken to Rogue's Roost, an island south of Greenland, where the Green Storm have converted Anna Fang's body into a Stalker. The commander, Sathya, hopes to restore Fang's memories by showing her Hester, but the resurrected Fang doesn't recognise her nor herself. Sathya reveals that, according to her intelligence, Hester's father was Thaddeus Valentine. After regularly drinking and the pressure of navigating to America, Pennyroyal miserably confesses that he never went to America, and based his entire book on an old explorer's map in the Reykjavík library. Tom later finds that the "ghosts" sighted around Anchorage are thieves, operating out of a parasite submarine-like limpet attached to the bottom of the city, who call themselves the Lost Boys and work out of a larger group in the sunken city of Grimsby. With their secret discovered, they kidnap Tom and leave the city. Tom develops a sort of friendship with a reluctant Lost Boy, Caul, on their trip to Grimsby. Caul tells him that the city is ruled by "Uncle": a man who founded it as a base of thieves. When they arrive in Grimsby Tom is taken to see Uncle, who tells him there is something valuable in Rogue's Roost, which he wants Tom to steal for him. In return, Tom will have the chance to rescue Hester. Tom climbs a ladder up the rocky cliffs to infiltrate the base; but is soon discovered and is reunited with Hester. Realising that Uncle sent Tom to die as a diversion, Caul prematurely detonates the charges the Lost Boys had planted; sabotaging the operation, but saving Tom and Hester. In their confusion, the Lost Boys make their way to the chamber where the Stalker Fang is kept, but the Stalker easily kills most of the Lost Boys, with only a few escaping with Caul kept prisoner. The Stalker Fang pursues Tom and Hester into the island hangar where the Jenny Haniver is kept, but lets them escape when she seemingly recognises Tom, and then takes command of the Green Storm forces from Sathya.

Part Three

In Grimsby, after being severely beaten for his betrayal, Caul is left to die by hanging by Uncle; who informs him that he knew Anna Fang when he was younger. Fang was a slave in Arkangel, but Uncle began to love her and released her. She betrayed him by building an airship and escaping from slavery. After Uncle was disowned by his family, he built Grimsby to make sure that nobody kept a secret from him ever again. Uncle wanted to retrieve Fang from Rogue's Roost to reprogram her to become his slave. Caul is saved by fellow Lost Boy Gargle, who wanted to repay Caul's kindness to him. Gargle gives Caul the Reykjavik map that Uncle had all along, and sends him back to Anchorage on a limpet.

Arkangel chases Anchorage, leading to the Huntsmen led by Masgard capturing Anchorage and leaving it helpless on the ice to be eaten; but Tom and Hester return to the city, where Pennyroyal has evaded capture. Hester sends Tom to hide, and later liberates the inhabitants and kills Masgard and the Hunstmen. Tom confronts Pennyroyal, who knows that Hester sold Anchorage to Masgard, but doesn't tell Tom. Attempting to scare Tom off, Pennyroyal accidentally shoots Tom in the chest. He then steals the Jenny Haniver with stolen Anchorage money, and escapes. Arkangel still pursues Anchorage, but becomes trapped over thin ice, leading Anchorage to drift on the ocean on an iceberg.

With the revelation that Pennyroyal is a fraud, the inhabitants lose hope in the salvation of their city, until Caul arrives with the Reykjavik map, and convinces them to continue. Meanwhile, Pennyroyal escapes to the Hunting Ground, and soon publishes a book reimagining the events of Anchorage's flight west, with himself as the hero and exposing the Lost Boys. Arkangel is evacuated and eventually sinks to the bottom of the ocean. In Asia, the Green Storm, under the leadership of the Stalker Fang, topples the old Anti-Traction League. Anchorage eventually makes it to North America, and finds it verdant and lush. Tom recovers from his wound, but is still very weak. Hester takes comfort in the knowledge that the city will be secret and safe in this new land, and is pleased to discover that she is pregnant.