Tom Natsworthy is the main protagonist of the Mortal Engines Quartet. An apprentice Historian at the beginning of the series, he eventually has diverse adventures across the world.
When he was twelve, he won a Guild prize for an essay on identifying fake antiquities.
By the time he was fifteen years old, Tom was a Third Class Apprentice, working under Chudleigh Pomeroy. He observed London's capture of Salthook, but was sent to the Gut after a brawl with Herbert Melliphant.
Tom was accompanied by his hero, Head Historian Thaddeus Valentine, as well as Valentine's daughter Katherine. Together, they approached the Salthook scavengers to purchase Old Tech. However, one was an assassin in disguise, and attempted to stab Valentine. Tom managed to stop the attack, and pursued the girl towards the furnace district.
The would-be killer revealed her name to be Hester Shaw. She claimed that Valentine was responsible for her disfigurement before leaping down a waste chute. Shortly after, Valentine arrived and to Tom's surprise, pushed him down after her.
Together, Tom and Hester trailed London, eventually being picked up by Speedwell. However, the mayor had the pair drugged with the intention of selling them as slaves. They managed to escape, chased by the slavers. They were rescued by Anna Fang, who smuggled them to Airhaven aboard the Jenny Haniver.
Tom, Hester and Anna dined at the Gasbag and Gondola inn, accompanied by several of her Anti-Tractionist friends. The dinner was interrupted by the arrival of Shrike, a Stalker sent by London mayor Magnus Crome to kill Hester. While the aviators held off Shrike, Tom and Hester escaped Airhaven on a hot air balloon.
The pair then climbed onto the pirate suburb of Tunbridge Wheels. Chrysler Peavey took a shine to Tom, considering him a "gentleman" for originating from London. However, the brutality of the pirates caused Tom to grow disillusioned with the concept of Municipal Darwinism. After Peavey's men mutinied, Shrike caught up with Tom and Hester. The Stalker revealed his intention to kill Hester and have her resurrected as his daughter, but before Hester could be executed, Tom stabbed and killed him.
Tom and Hester then reunited with Anna, who took them to Shan Guo to warn the citizens of MEDUSA. Tom spotted Valentine disguised as a monk, and raced to find Anna and Hester. Witnessing Valentine kill Anna, he resolved to return to London with Hester and help her kill the Head Historian.
Hester, meanwhile, was captured and taken to Valentine. However, she was freed after Katherine was stabbed and fell on MEDUSA's console, causing it to malfunction. She quickly left London with Tom in the airship. MEDUSA finally misfired, obliterating most of the city and killing Valentine. Hester tried to comfort a grief stricken Tom as they flew away in the Jenny Haniver, apparently the only survivors of the incident, and made their way to the Bird Roads.
After two years working as an air-trader alongside Hester, Tom came into contact with Nimrod Pennyroyal, an author who requested transport to Brighton. However, the Jenny Haniver was chased by the Green Storm, an organisation that regarded the ship as stolen. Tom flew the airship through the streets of Novaya-Nizhni to evade the pursuers, and although he was successful, the Jenny was heavily damaged. Eventually, the ship drifted towards Anchorage.
While the Jenny was being repaired, Tom and Freya Rasmussen, the margravine of the city, became infatuated with each other, resulting in a drunken kiss witnessed by Hester and Caul, a Lost Boy. Tom was later awoken by Caul in time to witness a distressed Hester take off in the Jenny.
Unable to convince Freya to turn back Anchorage, Tom spent his time investigating the burglaries occurring around the city. After a heated exchange with Pennyroyal, Tom realised that the author's books were complete fantasies- however, the idea of parasite towns was not. Tom was kidnapped by the Lost Boys upon discovering a spider-cam, and taken to Grimsby.
At the underwater lair, Uncle revealed that Hester was being held captive by the Green Storm at Rogue's Roost. Uncle offered the Lost Boys to take Tom there- ostensibly so that Tom could save Hester, and Uncle could spy on the Green Storm.
Tom was immediately attacked by Stalker Birds upon his arrival at Rogue's Roost, then captured. He was taken to Hester's cell by Sathya, one of Anna's old friends, and almost executed. However, Caul triggered the explosion of the spider-cams, cutting the power and ruining the base. Freed, Tom and Hester fled towards the Jenny Haniver. They were confronted by Sathya and the Stalker Fang, with Sathya encouraging the Stalker to kill them. Guided by vague memories of Tom's presence at Anna's death, the Stalker refused to do so, and allowed them to leave unharmed.
After returning to Anchorage, Tom came across Pennyroyal attempting to escape the city. Tom was accidentally shot by the author, who flew away in the Jenny.
Tom spent fifteen years living on a now static Anchorage with Hester and their daughter, Wren. After Wren was kidnapped by Fishcake, he journeyed with Hester, Caul and Freya to Grimsby. Learning that Wren had likely been trapped at Brighton, he then travelled there with Hester.
Tom explained his situation to slaver Nabisco Shkin, in the hope that Shkin would simply give his daughter back. Instead, Shkin imprisoned him and took his wedding band, coercing Wren into stealing the Tin Book of Anchorage. Hester broke into the Shkin Corporation, freeing him and Fishcake, but Tom was frightened by her brutal murder of the guards.
Tom and Hester regained the Jenny Haniver from a Pennyroyal-themed exhibition, and flew up to Cloud 9. They were successful, but Wren revealed how Hester had betrayed Anchorage to the Huntsmen. Despite Tom's pleas, a deeply shaken Hester walked off, and he was forced to fly away on the Jenny without her.
A Darkling Plain
After six months of travelling with Wren, Tom visited a heart specialist in Peripatetiapolis about chest pains he had been suffering. He learned that Pennyroyal's bullet had caused a weakness in his heart that gave him only a few years left to live.
In the Traction City of Peripatetiapolis, Tom Natsworthy discovers that the bullet that Nimrod Pennyroyal shot him with in Predator's Gold has damaged his heart and he has not long to live, though he doesn’t tell his daughter Wren. Tom soon discovers a woman that resembles Clytie Potts, a London Apprentice Historian that he knew. When questioned, she tells him that her name is Cruwys Morchard and that she is transporting Old Tech devices. Unconvinced, Tom and Wren decide to pursue her, travelling on the Jenny Haniver to Murnau, a Traktionstadtsgesellschaft city, where they meet Wolf von Kobold, the son of the Mayor of Murnau and commander of the traction city Harrowbarrow. Wolf believes that the survivors of MEDUSA may be still inside London, and the three agree to make an expedition to London.
Tom and Wren meet Wolf on Harrowbarrow, a burrowing Traction City, which takes them closer to London. With Wolf accompanying them, they fly the Jenny Haniver over the Green Storm border, and finally reaching the debris field of London. There they discover that the survivors of MEDUSA have rebuilt a society in London, led by Tom’s old boss and now Mayor Chudleigh Pomeroy. Garamond, the paranoid head of security, convinces Pomeroy to keep them there as he suspects that they may inform others of London’s survival. Tom, Wren and Wolf eventually discover a new traction town being rebuilt near the ruins, a project that was in-progress long before Magnus Crome decided to use MEDUSA.
Tom, fearing for Wren, takes the Jenny Haniver to Tienjing, hoping to convince Naga to not use his supposed weapon. Tom leaves a letter to Wren saying his goodbyes and entrusting Theo to take care for her, admitting that he is dying. Wolf hears of Manchester’s destruction and is determined to continue on to London, claiming to his underlings that Harrowbarrow’s creeping nature will help them survive.
On-board the Jenny Haniver, Tom forgives Hester for selling Anchorage to Arkangel. Shrike finds Pennyroyal hiding, and the three tie him up. Stalker-birds attack the airship, severely damaging it. Shrike manages to save the three from being killed, but falls out of the ship and into the mountains. The airship downs near Fang’s old home, where Hester and Tom leave Pennyroyal. Fishcake, having heard the airship, confronts them and tries to kill Hester; but is stopped by the Stalker Fang. Fishcake demands she kills them, but the Stalker Fang hits him and Fishcake runs away. Tom’s heart begins to strain and he collapses. The Stalker Fang, deciding not to kill them as they will all die soon enough, takes Tom into the house as Hester follows.
The Stalker Fang explains to Tom and Hester that she destroyed various traction cities and Green Storm bases to make the two sides fight each other, giving her time to send a command to ODIN. This command targets the various destructive volcanoes around the Earth, which will erupt and kill mankind, but will "make the world green again". Fishcake finds Pennyroyal, and they plan to escape in Popjoy’s sky-yacht, but need the keys around the Stalker Fang’s neck. Pennyroyal finds an Anti-Stalker weapon that Hester dropped and makes his way toward the house. Tom attempts to convince the Anna-side of the Stalker to destroy ODIN, and the Stalker flashes between the converging personalities. Tom’s heart strains and he collapses again, whilst Pennyroyal takes the key to the sky-yacht and attempt to bring it to them to save Tom. As Hester carefully takes Tom outside, they see a twinkling star in the sky: ODIN destroying itself. Hester realises that the Stalker Fang had ordered the weapon to destroy itself. Pennyroyal attempts to fly the sky-yacht to Tom and Hester, but is threatened by Fishcake to leave them behind as revenge for leaving him on Brighton
As he lay dying, weakly, Hester slowly drags him to a villa. Hester thinks there is no way out, but soon comes to terms and accepts there there is one way out.
Tom lays there. He did not care what happened as he thinks to himself as lucky he was loved by someone so strong, and brave, and beautiful. The last thing he ever heard was What Hester said: "It will be all right, Tom. Wherever we go now, whatever becomes of us, we'll be together, and it will be all right." Tom dies with Hester by his side. Hester commits suicide to join Tom. Shrike runs to them, but it was too late. He moves their bodies to a cave in Erdene Tezh, holding hands. Shrike stays with them until nature consumes their bodies. Tom and Hester are remembered when Shrike came out of his slumber and tells their story.