Trailblazing scientists are making ground-breaking discoveries in the rapidly evolving world of genetic engineering. Technologies like CRISPR are making it possible to quickly and cheaply change the DNA of all living things, including humans. Today, genes can be edited almost as easily as words on a computer screen. This new ability to alter our DNA holds the promise of curing disease, saving threatened species, solving the problem of world hunger and maybe even obtaining human perfection. But will the promise be fulfilled and at what cost?