Marine biologist Monty Halls explores the challenges facing the British fishing industry by living and working as a traditional Cornish fisherman. In rough seas, he heads out to work on the biggest crabber on the coast, the Harvester, which has 1,800 crab pots. And he discovers that while the British have no appetite for his tasty Cornish spider crabs, the French cannot get enough of them.

• Monty Halls