Two years on since Monty Halls, his wife Tam and daughters Isla and Molly first travelled to the Galapagos islands, the family head back to discover why it faces a fight for survival. In the opening episode, Monty experiences the mighty volcanic power that created the islands, mum Tam makes a solo voyage in search of threatened giant manta rays, and Molly, the youngest, has her first snorkelling experience.

• Monty Halls