There are certain medical advances that have improved the overall quality of modern life by such degrees that civilisation seems unthinkable without them. Antibiotics certainly fall into this category. Infections that used to be life threatening for the biggest part of human history can now be treated with ease, thanks to penicillin and other antibiotics that revolutionised medicine in the 20th century, but our excessive overuse of these wonder-drugs in humans and animals has led us to a dangerous point in history. With the development of antibiotic-resistant superbugs, this medical cornerstone is slowly crumbling away, threatening to take us back to the Middle Ages. Already today, infections involving ultra-resistant bacteria kill about 57,000 newborn babies in India every year and antibiotic-resistant bugs claim more lives in the UK (around 12,000 people) than breast cancer. Timothy Walsh, Professor of Medical Microbiology and Antibiotic Resistance at Cardiff University, has been at the forefront of this issue for years. His work on the usage of colistin, a “last-hope antibiotic” in agriculture and medicine, has been instrumental in outlining the danger of a post-antibiotic future in which any small scratch can lead to death and where caesarean sections and chemotherapy would become nearly impossible. At Falling Walls, Tim explains how we managed to get so close to the post-antibiotic apocalypse and what we can do to avert it.