Ben Howard

To June's despair, Terry has become a wine-making enthusiast. She persuades him that a visit to Boulogne for some duty-free would be more enjoyable.

In Wales, a dead miner is found glowing green. UNIT investigates as Jo empathises with the environmentalism of Cliff Jones, who is opposing the pollution from the company, Global Chemicals.

The Brigadier attempts to seal the giant maggots in the mine with explosives, but this only results in the creatures burrowing to the surface. Meanwhile, the Doctor is trapped by the real boss of Global Chemicals.

The Doctor and Jo discover the mine's terrible secret. Global Chemicals' managing director, Stevens, is determined to make sure that the two of them won't live to reveal what they have learnt.