Crystals form in storm clouds, metals, drug molecules, and even in diseased tissues. Despite their ubiquity, scientists still don’t fully understand what happens when a liquid solution first starts to form a solid crystal, a step called nucleation. Now researchers have gotten their first glimpse of the details of the process, imaging individual atoms during nucleation in metal nanoparticles (Nature 2019, DOI: 10.1038/s41586-019-1317-x).