Back in the 1990s, a young microbiologist in Alicante, Spain became obsessed with a strange pattern he observed in the genes of tiny organisms — a series of inexplicable clusters. And he wasn’t alone. All around the world, a network of scientists were growing curious as to what these genetic knots could be and all of their potential functions. Their curiosity would prove to be the foundation for a history altering discovery: the ability to edit our genetic code.