Bill explains how the ocean affects climates in different parts of the world. He mentions the Gulf Stream and how it keeps Britain much warmer it would be otherwise. He also explains El Nino and how it affects the climate of the Americas.

Jack describes the ancient climate shift known as the Younger Dryas. He states that, as the world was coming out of the last glacial period, melting ice sheets added so much freshwater to the Atlantic Ocean that certain ocean circulation patterns shut down. Since thermohaline circulation is a major source of heat for the surfaces of continents, the globe was plunged back into an ice age.

The crew is in the middle of a terrible storm and takes a risk to head into the eye. They decide to turn around and head in a safer direction, but they encounter an enormous rogue wave and cannot escape from it in time.

Bill Nye explains that thermohaline currents are created by warm and salty water sinking and rising in the ocean. Water with a higher concentration of salt is more dense and thus sinks into the ocean.

After a long journey, Mr. Bean finally reaches the beach. Using his camcorder, he records the shoreline and the activities taking place on the beach.