The Happy Pigs. By Lucy Harkness. The Blackstaff Press. 244pp. £7.99 in UK

The cheerful pigs of the title of Lucy Harkness's first novel refer to the infamous public nickname given to the police. The protagonist, policewoman Louisa Barratt, has been in the force for six years, and is now serving with the Child Protection Unit in King's Cross.

This is the story of what happens to Louisa, both in her personal and professional life, after a man attempts to rape her in a London alleyway. It doesn't spoil the story to relate that the would-be rapist turns out to have been a colleague: this fact is revealed early on in the novel.

Harkness writes from the perspective of one who knows her field: she herself has worked for the British Transport Police in London for several years. The novel certainly draws a convincing behind-the-scenes portrait of the policing world, and Louisa Barratt is an interesting and believable character.

Reading between the lines, you also get the impression that Harkness is as anxious to make several points about society's failure to protect its most vulnerable members - such as abused children - as she is to create a work of fiction. Her biographical note tells us that she is currently retraining to be a lawyer.

However, as well-written and researched as her novel is, plot and pace just don't last the distance. The Happy Pigs has more the feel of an excellent long short story that forgot to stop.