"Everybody pees and poops — and we know that urine and stool contain a rich source of information on our health," says data detective Newsha Ghaeli. Exploring the growing field of wastewater epidemiology, she shows how studying sewage can (anonymously) reveal a lot about the collective well-being of our cities — leading to real-time quality-of-life improvements like tracking pandemics, updating social policies and much more.