Taking us beyond the confines of our own experiences, The Color of North traverses the kingdom of life to uncover the myriad ways that proteins shape us and all organisms on the planet. Inside every cell, a tight-knit community of millions of proteins skillfully contorts into unique shapes to give fireflies their ghostly glow, enable the octopus to see predators with its skin, and make humans fall in love. Collectively, proteins orchestrate the intricate relationships within ecosystems and forge the trajectory of life. And yet, nature has exploited just a fraction of their immense potential. Shahir S. Rizk and Maggie M. Fink show how breathtaking advances in protein engineering are expanding on nature’s repertoire, introducing proteins that can detect environmental pollutants, capture carbon dioxide from the atmosphere, and treat diseases from cancer to COVID-19.