Michelle McNamara and her editors agree to push her book deadline after being granted access to the Orange County Sheriff's Department's East Area Rapist / Original Night Stalker room. After everybody realized the killer moved south, that story exploded. The hope was that by having greater public attention, the right person gave the right tip.

To survive Mars, our species will need to evolve how we eat, drink, and build our homes. Will we need our genes to evolve as well? Sometime in the future humans will leave Earth to colonize Mars, and in doing so will begin to adapt to life on another planet in surprising ways. Evolutionary biologist Dr. Scott Solomon foresees a series of changes to our species from the size of our hearts and heads to the pigments in our skin.

Edgar Davidson agrees to talk to investigators but tells a different story. Cathy’s sister Marilyn indicates her interest in solving the case. Tom Nugent casts doubt on Gerry Koob’s story about the night of Cathy’s disappearance. The search for the other man at Cathy’s apartment Pete McKeon may have information about Koob’s relationship.
What Cathy’s roommate Sister Russell knew about the abuse and Cathy’s relationship comes into question. 'Jane Doe' and 'Jane Roe' meet for the first time and talk about the Keough. Abbie investigates Baltimore’s investigation into the abuse reports they received. Marilyn Cesnik Radakovic recalls receiving a mysterious letter from her sister after her death.

Science may soon make the dream of traveling to Mars a reality, but how will we live once we get there? How will we manage our basic human needs of food, water, and shelter on a planet known for its barren surface conditions, high radiation levels, and toxic dirt?

A mammoth Tsunami strikes the eastern seaboard. It would be a disaster of epic proportions. Some scientists believe this catastrophe could happen one day, but how? This episode shows the Atlantic island of La Palma has collapsed several times in mega-landslides. Another could trigger a tsunami with enough power to cross the Atlantic Ocean and decimate the US East Coast.

Beneath Yellowstone National Park, lies the biggest volcano on Earth. An eruption in the past was so big it plunged the earth into a volcanic winter that lasted years. A super-eruption would be more than millions of Hiroshima bombs going off all at once. It would be even worse than an asteroid impact: Entire cities lost beneath ash, people and animals crushed alive, power networks destroyed, sun dimmed across the globe, harvests failed, widespread famine. Could this nightmare really happen? We will use the latest scientific data to uncover the danger beneath us, as we see our planet like never before.