The Hale-Bopp Comet is passing Earth and rumours of a mysterious object following the comet could mean the sign that the Heaven’s Gate community could be looking for. With plans for the Exit, the group members begin saying goodbye to the world. In the aftermath of the suicides, the world and the surviving former followers react.

The message of the group begins to change and losing identity and group mentality is pushed. With more lockdowns and rules, longtime members of the group begin to question or leave. With no sex permitted with members, Dick Joslyn’s membership in the cult poses problem for Do... leading to a new request for the group.
With dwindling numbers, the group needs a new boost of membership. The Exit begins to be discussed as the Hale-Bopp Comet approaches.

Some 65 million years ago, the dinosaurs were wiped out when their gene machines failed to cope with the cataclysmic changes that followed a comet's collision with Earth. But with extinction came new life, and surviving mammals evolved to seize the territory left vacant by the vanquished. The concluding episode explores the factors that make winners and losers in the game of life, and poses the question: Who will triumph in the long run?

The episode begins with Tyson describing how pattern recognition manifested in early civilization as using astronomy and astrology to predict the passing of the seasons, including how the passage of a comet was often taken as an omen. Tyson continues to explain that the origin of comets only became known in the 20th century due to the work of Jan Oort and his hypothesis of the Oort cloud. Tyson then continues to relate the collaboration between Edmond Halley and Isaac Newton in the last part of the 17th century in Cambridge. The collaboration would result in the publication of Philosophiæ Naturalis Principia Mathematica, the first major work to describe the laws of physics in mathematical terms, despite objections and claims of plagiarism from Robert Hooke and financial difficulties of the Royal Society of London. Tyson explains how this work challenged the prevailing notion that God had planned out the heavens, but would end up influencing many factors of modern life, including space flight. Tyson further describes Halley's contributions including determining Earth's distance to the sun, the motion of stars and predicting the orbit of then-unnamed Halley's Comet using Newton's laws. Tyson contrasts these scientific approaches to understanding the galaxy compared to what earlier civilizations had done, and considers this advancement as mankind's first steps into exploring the universe. The episode ends with an animation of the Milky Way and Andromeda galaxies' merging based on the principles of Newton's laws.