In 132 CE, Zhang Heng presented his latest invention: a large vase he claimed could tell them whenever an earthquake occurred for hundreds of miles. Today, we no longer rely on pots as warning systems, but earthquakes still offer challenges to those trying to track them. Why are earthquakes so hard to anticipate, and how could we get better at predicting them? Jean-Baptiste P. Koehl investigates. [Directed by Cabong Studios, narrated by Addison Anderson, music by Matheus Wittmann].