Experience the greatest breakthroughs in science, with the DK Science Stories series.

On the battlefields of World War I, soldiers are dying from infected wounds. A young doctor witnessing the devastation vows to find a cure. In his messy laboratory a decade later, he makes an accidental discovery – a miracle mould that kills bacteria. But try as he might, he cannot turn his amazing find into a useful medicine.

This is the story of that chance discovery and the brilliant scientists who took Alexander Fleming’s miracle mould and worked tirelessly to turn it into a treatment that doctors could use. As another war broke out in Europe, they found themselves in a race against time to grow enough penicillin and create the first antibiotic. Their teamwork and determination led to a class of drugs that saved countless lives and paved the way for modern surgery and other life-saving treatments.

Isabel Thomas is an award-winning science writer, presenter, and educator. She has degrees in Human Sciences from the University of Oxford and Educational Research from the University of Cambridge. Isabel has written a galaxy of books for young audiences, and is a double winner of the AAAS Prize for Excellence in Science Books. She also writes features for science magazines and the BBC, and delivers outreach projects for a wide range of organisations, inspiring children from diverse backgrounds to pursue science. You can find more about Isabel and her work at isabelthomas.co.uk.

© 2025 Isabel Thomas (P) 2025 DK Audio