As their stay on the Galapagos draws to a close, Monty Halls and his family find out what's being done to protect the islands and their endangered wildlife from the threat of invasive animals. Monty embarks on a dangerous mission in search of an undiscovered species, daughters Isla and Molly get a glimpse of what the future might hold, and Tam braves a perilous rock face to help save the Floreana mockingbird from the brink of extinction.
