In the vibrant heart of New York City, a young math enthusiast named Annika stumbles upon a perplexing mystery: prime numbers are vanishing across the city, from street signs to digital displays. Accompanied by her three cats, Annika uses her sharp mind and mathematical prowess to investigate this bizarre occurrence. Her journey leads her to confront a reclusive mathematician who has been collecting prime numbers, believing they hold a universal secret. Together, they work to restore the numbers and transform their findings into a public garden, designed to represent the elegance and distribution of prime numbers. Annika's adventure not only solves the mystery but also turns it into a celebration of mathematical knowledge, inspiring those around her to see math as a thrilling adventure. This tale is a captivating blend of mystery, mathematics, and the unyielding curiosity of a young girl in the big city.