In 1941, Swiss electrical engineer George de Mestral returned from a hunting trip in the Alps with his trousers and his dog covered in burdock burrs. Rather than throw them away, he put one under a microscope and found hundreds of tiny stiff hooks snagging the loops of fabric and fur. This episode follows how that moment of curiosity became a decade-long engineering struggle to build a hook-and-loop fastener, from the weavers in Lyon who called the idea impossible to the switch from cotton to nylon and the discovery that infrared heat could set thermoplastic hooks.

We cover the low-tech breakthrough of trimming the loops with scissors, the eight years spent building a loom for the hooks and another year for a trimming machine, the 1951 Swiss patent and the name blended from velours and crochet. Then comes the commercial flop with the fashio ...