Neil works with a team of scientists and marine mammal toxicologists on an expedition to prove the presence of deadly toxins inside Bermuda's mid migratory humpback whales. They collect biopsy samples from 50 ton humpbacks using an adapted compound bow. The team also deploy their aerial drone to observe a mother humpback and calf, and Choy has a dangerous encounter when he receives a report of a dead sperm whale being torn to shreds by hungry sharks.