Mary Cholmondeley (1859-1925) was an English novelist and short story writer. 'Let Loose' is a supernatural ghost story where a young architect wishes to research a unique fresco in the crypt of a remote and ancient parish church in Yorkshire.

The parish clergyman is remarkably reluctant to hand over the keys to the crypt and sets some odd conditions to their use. On the subsequent days after the young architect has opened the crypt, terrible and mysterious deaths begin to plague the village. Something has been let loose...something horrible and sinister....