A blank spot on a digital map can signal much more than a gap in data — it can mean something is being intentionally hidden. Sharing the remarkable discovery of massive alleged detention camps in Xinjiang, China, Pulitzer Prize-winning journalist Alison Killing shows how governments can obscure human rights abuses by limiting journalist access on the ground — and calls for more reliable open-source data (like satellite and social media imagery) to shine a light on the world’s darkest places.