Doomwatch

British sci-fi thriller based on the 1970s BBC series.

The film follows Dr. Del Shaw (Ian Bannen) of the government's investigative environmental organisation Doomwatch as he travels to the island of Balfe to examine the potentially adverse effects of a recent oil spill.

The villagers are all suspicious of Shaw, especially the menfolk, who seem to have transformed into near-Neanderthals.

Samples of the local fish sent back to Doomwatch prove to be unnaturally large, and after teaming up with a local teacher, Shaw discovers that the transformation of the men is due to a disease called acromegaly.