Liz Bonnin continues her voyage around the Galapagos Islands on board the research vessel Alucia.

She and the team are studying sunfish, the world’s largest bony fish, and they’re also keen to track hammerhead sharks, endangered because of the shark-fin trade.

The scientists are optimistic they’ll find them, but the submersible will need to venture into a treacherous area.

Nothing can prepare Liz for the dive she’s about to experience…