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

About

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

Author

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