What happens when sunlight meets an enzyme? Is it love at the first sight? Light-driven reactions were probably the very first happening on primordial Earth and contributed to generating the reservoir of prebiotic molecules necessary to the evolution of life. Since then, light and photosynthesis have produced everything we admire in nature, a 3.4-billion-year-old marriage (still on-going). This is the manual to look at if we want to harness the very first source of renewable energy available. In my research lab we couple light energy to enzymes that can transform bio-resources into useful biomolecules, biomaterials, and biofuels.