The Opening of the Gump and the Prince's Disappearance
Every nine years, a hidden gump (a magical portal) beneath Platform 13 of London's King's Cross Station opens, connecting the magical Island to the human world for nine days. During one such opening, the King and Queen of the Island send their infant son, Prince Florian, through the gump to visit the human world under the care of his nursemaid. However, the nursemaid is distracted by a runaway dog, and a greedy, childless woman named Mrs. Trottle, accompanied by her timid husband, spots the unattended baby. Mrs. Trottle snatches the baby and flees into the London crowds. The heartbroken nursemaid returns to the Island with only the prince's silver rattle.
Nine Years Later: The Rescue Mission is Formed
Nine years later, as the gump is about to open again, the King and Queen of the Island want to retrieve their now-nine-year-old son. They assemble a rescue party: a huge, gentle ogre named Gurkintrude, a powerful but short-tempered wizard named Cornelius, a wise but grumpy fey named Merrow, and a fierce, loyal hag named Mrs. Screech. Their mission is to travel through the gump to London, find Prince Florian, and bring him back to the Island before the portal closes for another nine years. The King gives them a magical golden compass that points towards the prince, and they prepare for their journey into the human world.
Arrival in London and Initial Struggles
The rescue party emerges from the gump into the bustling, grimy King's Cross Station. They are immediately overwhelmed by the noise, the crowds, and the strangeness of the human world. Their magical abilities are somewhat hindered, and their unusual appearances draw unwanted attention. They struggle to navigate the city, initially using Mrs. Screech's unreliable broomstick and later walking. The golden compass points them towards a wealthy area of London, leading them to suspect the prince is living a life of luxury, far removed from his true heritage.
Discovering Raymond and the Trottles' Opulence
Following the golden compass, the rescue party eventually arrives at a grand, imposing house belonging to the Trottle family. They observe the family and quickly deduce that the Trottles have adopted the lost prince. However, they are shocked to find that the boy, now named Raymond Trottle, is an incredibly spoiled, selfish, and cruel child, constantly demanding attention and mistreating everyone around him, especially his timid parents. The rescuers are appalled by his behavior, which is a stark contrast to the kind and noble nature expected of an Island prince. They realize that Raymond has been raised in a completely different way than they anticipated.
The Introduction of Odile and Her Kindness
While observing the Trottle household, the rescuers notice a young kitchen maid named Odile. She is kind, hardworking, and constantly subjected to Raymond's cruelty and Mrs. Trottle's demands. Odile secretly cares for a collection of small, magical creatures that have inadvertently followed the rescue party from the Island, including a small, mischievous ghost and a tiny merrow. She shows compassion to these creatures and to an old, neglected dog. Her gentle nature and empathy stand out in the harsh environment of the Trottle home, making her a potential ally for the rescue party.
Attempts to Abduct Raymond and Growing Doubts
The rescue party makes several attempts to abduct Raymond, believing him to be Prince Florian. Each attempt is thwarted by Raymond's cunning, his parents' overprotectiveness, or the rescuers' unfamiliarity with human customs. During these attempts, they see Raymond's increasing nastiness firsthand. His selfishness, his tantrums, and his complete lack of empathy for anyone, including animals, make the rescuers doubt if such an unpleasant child could truly be their beloved prince. They begin to wonder if there has been a mistake, as his character is so different from the noble qualities of the Island's royal family.
Odile's Discovery and the Truth Revealed
Odile, while cleaning Raymond's room, discovers a hidden compartment in a toy chest. Inside, she finds a dusty, old silver rattle and a faded baby blanket – the very items that belonged to the lost prince. She also overhears Mrs. Trottle confessing to her husband that she swapped her own sickly, human baby (who later died) for the healthy, magical baby from the Island nine years ago. This revelation confirms that Raymond is not the prince; the true prince was given to a poor family by Mrs. Trottle. Odile, realizing the injustice, decides to help the magical beings find the real prince.
The Search for the Real Prince and His Humble Life
With Odile's help, the rescue party uses the golden compass, which now points away from the Trottles' house, to search for the real Prince Florian. The compass leads them to a humble, working-class neighborhood. They discover a kind, gentle, and resourceful boy named Fred, who lives with a loving but poor family. Fred possesses an innate kindness, a talent for animal communication, and a natural affinity for magic, even though he is unaware of his true heritage. The rescuers immediately recognize the noble qualities that Raymond lacked, and they are convinced that Fred is their lost prince.
The Race Against Time and Mrs. Trottle's Interference
As the gump's closing time approaches, the rescuers, now accompanied by Fred and Odile, race back towards Platform 13. However, Mrs. Trottle, realizing her deception is exposed and fearing exposure, tries to stop them. She alerts the police and tries to block their path, desperate to prevent Fred from reaching the gump. A chaotic chase follows through the streets of London, with the magical creatures using their abilities to evade capture and protect Fred. The fate of the prince and the Island hangs in the balance as they near their destination.
Return to the Island and a New Beginning
Just as the gump begins to flicker and shrink, the rescue party, with Fred safely in tow, bursts through the portal onto Platform 13. They narrowly escape Mrs. Trottle and the human world. On the Island, Fred is joyfully reunited with his true parents, the King and Queen. He quickly adapts to his magical heritage, embracing his role with grace and kindness. Odile, who bravely assisted them, is offered a place on the Island, where she finds happiness and belonging among the magical creatures. The gump closes, leaving the Island's secret safe once more, and everyone, except the Trottles, finds their rightful place.