A fascinating look at the Cascadian Subduction Zone in the Pacific Northwest, where scientists predict a major earthquake will occur at some point in the next 100 years, starts with terrific, accessible explanations of plate tectonics and subduction earthquakes. Readers meet researchers looking for evidence of past subduction earthquakes and resulting tsunamis in the region, work that includes scientific research on land and in water, and studying the oral histories of Indigenous communities in the Pacific Northwest and recorded and oral histories in Japan. This account also introduces individuals devoted to mitigating the impact of a major earthquake in the future, from engineers determining how best to reinforce bridges and buildings, to individuals working on the ShakeAlert seismic monitor and notification system. The annual Disaster Relief Trial biking event in several northwest cities mimics post-quake devastation to practice how everyday citizens, including teens shown here, can play a role in emergency response. The sobering reality of a likely natural disaster is balanced here by human effort, ingenuity, and commitment to understanding the past and preparing for the future. (Age 11 and older)