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.