 Two English cartographers visit the small South Wales village of Ffynnon Garw, to measure what is claimed to be the "first mountain inside of Wales". It s 1917, and the war in Europe continues. The villagers are very proud of their "mountain", and are understandably dissapointed and furious to find that it is in fact a "hill". Not to be outwitted by a rule (and the Englishmen who enforce it), the villagers set out to make their hill into a mountain, but to do so they must keep the English from leaving, before the job is done.