This educational video provides a comprehensive overview of the geological processes occurring beneath the ocean's surface, specifically focusing on plate tectonics, seafloor spreading, and subduction. The presenter explains how Earth's most extreme landscapes, such as the Mariana Trench and mid-ocean ridges, are formed through the movement and interaction of tectonic plates. The video uses clear animations and comparative examples to illustrate how new crust is created at divergent boundaries and destroyed at convergent boundaries.