First Nation scientist Andrea Megin studies giant squid in the South Pacific by sending cameras, suctioned to backs of diving sperm whales, into the deep ocean. Josh Templeton, a marine biologist, joins Andrea's team aboard the research ship after following a rare, old sperm whale from Hawaii to the Galapagos Islands. Together, they explore Earth's last frontier and discover a terrifying reality. They must risk everything to save the whales, their tumultuous relationship, and life on Earth.