A young girl named Mary moves to the countryside to live with her Great-Aunt Charlotte. Struggling with boredom and loneliness, she stumbles upon a mysterious flower known as the "Fly-by-Night." This peculiar flower grants her temporary magical powers, including the ability to fly on a broomstick. During one of her broomstick flights, she discovers an enchanted college called Endor College for witches and magic users. Welcomed warmly by the headmistress Madame Mumblechook and the brilliant Doctor Dee, Mary becomes enthralled by the wonders of this hidden world of magic.

Despite the initial enchantment, she soon realizes that the magic offered by Endor College comes with dangerous secrets. Mary uncovers a strange and sinister plot that puts both the magical world and her own at risk. As she delves deeper into the truth behind her newfound powers and the intentions of Madame Mumblechook and Doctor Dee, Mary is thrust into a race against time to set things right. Alongside newfound allies and her loyal cat, Tib, Mary faces a journey filled with challenges that test her courage and resolve, defining her path beyond what she could have ever imagined.