The Book of 528: Prosperity Key of Love by Dr. Leonard G. Horowitz is a non-fiction work that explores the "528Hz" frequency as a fundamental, Divine, and creative energy that can heal individuals, society, and the planet. The book posits that 528Hz is the "Miracle note" of the universe, a musical mathematics that serves as a remedy for contemporary social, environmental, and healthcare crises. The book is aimed at offering a "paradigm shift" in every industry and helping humanity to evolve by embracing the frequency of love, often contrasted with a modern world full of anxiety and irrational fears.