This film explores the foundational research in the Serengeti National Park, Tanzania, that uncovered many of the ecological principles that govern how animal populations and communities are regulated.

This is the story of how ecologists Tony Sinclair, Simon Mduma, and Grant Hopcraft spent five decades piecing together the mystery of what makes the Serengeti the way it is and the central role wildebeest play. The film is divided into three main chapters. Chapter 1 explores the phenomenon of the sudden increase in wildebeest and buffalo populations and connects to the concepts of top-down and bottom-up regulation and carrying capacity. Chapter 2 explores how migration allows wildebeest to reach enormous numbers. Chapter 3 explores how wildebeest indirectly affect many other components of the ecosystem, making them a keystone species. The film can be watched in its entirety or as standalone chapters.