The article discusses the potential of naturally occurring hydrogen reserves as a clean energy source to address the limitations of current hydrogen production methods, which heavily rely on oil and gas reforming, contributing to global CO2 emissions. Scientists from the University of Oxford, Durham University, and the University of Toronto propose a new approach to tap into Earth's geological hydrogen reserves, which have accumulated over millions of years. The review outlines various crustal reactions that produce hydrogen, including serpentinization, radiolysis, and organic shale maturation, highlighting the importance of suitable crustal settings for trapping hydrogen. Real-world examples like the accidental discovery of high hydrogen levels in water wells hint at the potential for significant hydrogen fields to be found through targeted exploration. The research team has launched Snowfox Discovery Ltd. to identify societally significant hydrogen fields by integrating geophysics, geochemistry, microbiology, and reservoir engineering. The study emphasizes the need for a repeatable exploration recipe to unlock commercially competitive, low-carbon hydrogen sources that can contribute to the energy transition. If successful, extracting natural hydrogen could serve as a bridge between current blue and green hydrogen production methods, diversifying the clean energy portfolio and reducing the burden on renewables. However, responsible extraction is crucial to prevent environmental damage, requiring stringent regulations to monitor leaks, protect groundwater, and manage co-produced gases. Overall, exploring Earth's hidden hydrogen reserves presents an opportunity to advance the energy transition while aligning with environmental sustainability goals.