"Secrets of Size: Atoms to Supergalaxies" is a two-part feature length documentary presented by Professor Jim Al-Khalili that explores the universe across extreme scales, using advanced technology to reveal the hidden patterns and invisible forces connecting the microscopic world of atoms and quantum physics with the vastness of galaxy clusters and superclusters. The first part delves into the unimaginably small, examining subatomic particles and the rules of quantum physics, while the second part ventures into the unimaginably large, exploring the immense structures and gravity that shape the cosmos.