As the Blitz wreaks havoc over London in August 1940, three orphaned siblings—Charlie, Carrie, and Paul Rawlins—are taken away from the war-torn city to the serene countryside of Pepperinge Eye, situated near the picturesque Dorset coast. Here, they find themselves under the temporary guardianship of the indecisive Miss Eglantine Price, portrayed by Angela Lansbury, who harbors her own secrets. Initially, the children's desperation drives them to consider fleeing back to London. However, after witnessing Miss Price’s clumsy attempt at flying on a broomstick, their plans undergo a change. This moment catalyzes an unexpected series of events when Miss Price discloses that she is learning witchcraft through correspondence courses, aiming to use her newfound abilities to assist Britain in its fight against the Nazis.
In return for the children's discretion, Miss Price offers them a unique transportation spell, which she awkwardly channels through a bedknob — but with a curious catch: it can only be used by Paul, due to his earlier act of handing the bedknob to her. As they acclimate to their tranquil new home, Miss Price receives a disheartening letter indicating that her correspondence school will be closing, leaving her unable to master the final spell she needs for her magical endeavors. In a moment of urgency, she persuades Paul to use the enchanted bedknob to make a return trip to London, seeking out Professor Emelius Browne, played by David Tomlinson.
Once they arrive in London, they encounter a charming street magician named Browne, who, unbeknownst to him, has stumbled upon genuine magic through an old book. Initially elated by this revelation, he is taken aback when he discovers that the spells indeed function. Miss Price receives the magical tome from Browne, but her excitement is short-lived as she realizes that the crucial final spell, Substitutiary Locomotion, is absent. Determined to reclaim their quest, the group sets off to Portobello Road to locate an old bookseller who had originally supplied Browne with the enchanting manuscript.
Their interactions with the bookseller reveal the chilling lore surrounding the Star of Astaroth, a mysterious medallion formerly owned by a sorcerer named Astaroth. The history recounts Astaroth’s dangerous experiments with magic on animals, endowing them with human-like traits, and his eventual downfall at the hands of his own former disciples, who fled to a secluded island called Naboombu, leaving only myths in their wake.
Paul’s exploration of a vintage storybook within Browne’s playroom establishes a tangible connection to the magical realm they are delving into, not only corroborating the existence of Naboombu but also stoking their adventurous spirit to uncover further mysteries.
As their journey to Naboombu unfolds, they face unforeseen challenges—their enchanted bed, now adrift at sea, accidentally becomes a winning entry in an underwater dance contest, thanks to the spectacular moves of Mr. Browne and Miss Price. The sudden intervention of a bear, who discovers the bed floating in the lagoon, starkly illustrates that the island has a strict "no humans" policy enforced by royal decree. The group is subsequently summoned before King Leonidas, who, adorned with the Star of Astaroth, proposes that Mr. Browne referee a high-risk football match. In the midst of the pandemonium, the match concludes with Leonidas claiming victory, but Browne cleverly swaps his referee whistle for the king's coveted medallion, enabling the group to make their escape.
Back in the safety of their familiar environment, Miss Price unleashes the full extent of her Substitutiary Locomotion spell, breathing life into inanimate objects. While this newfound power initially ignites excitement, chaos soon ensues as the objects begin to spiral out of control, threatening the very fabric of existence. Confronted with the possibility of the children needing to be relocated, Miss Price gradually recognizes the profound emotional bonds she has formed with them. As the group grows closer, Browne grapples with his feelings about his new family, ultimately saying goodbye. However, destiny intervenes when he finds himself at a railway station, where danger arises in the form of Nazi German operatives.
With enemy forces encroaching on the coast via submarine, Mr. Browne must step up, battling two German agents who aim to disrupt crucial communication lines. After ensuring his safety, he returns to Miss Price's home, where he discovers his latent magical abilities. Using his powers, he transforms into a white rabbit, blending in seamlessly to evade capture. Once his mission is accomplished, Mr. Browne reunites with Miss Price and the children at a local museum, only to find themselves trapped by the invading soldiers.
Galvanized by the bravery of her friends, Miss Price invokes her Substitutiary Locomotion once again, animating the museum's displays in an epic display of courage. A legion of suits of armor and military outfits emerges, set on expelling the German soldiers and reclaiming their safe haven. While the enemy ultimately retreats, they inflict significant damage on Miss Price's workshop, bringing her career as a witch to a heartbreaking conclusion. Despite this loss, she finds comfort in having played an essential role in the war effort, filling her with gratitude.
As time progresses, Miss Price embraces her new role as a guardian for the children, solidifying a momentous change in her life characterized by dedication to her newfound family. Meanwhile, Mr. Browne’s enlistment in the military means he must leave the small town, joined by the local Home Guard. In a tender farewell, he shares a kiss with Miss Price, assuring her that he will return to reclaim his place in their lives.
In this touching scene, Paul’s presence serves as a gentle reminder of their magical adventures together and the ever-enigmatic bedknob that facilitated their journey. Unspoken possibilities for future exploits linger in the air, hinting at more enchanting tales to unfold, leaving audiences eagerly anticipating the next chapter for this extraordinary group.
