Helen Fitzgerald's Halfway House is a thriller that’s hard to resist

(Orenda, £9.99)

Do we like Lou O’Dowd? I’m not sure. Her sole experience of employment, other than a stab at waitressing, seems to be as the kept woman of a sugar daddy, who gave her a Melbourne apartment to live in and money to fund her lifestyle. (As she only needed to spend six hours a week in his company, she figured it was a good deal.)

Lou regards friendships as being like romances, in that they reach a peak and then naturally draw to a close. She has a taste for “bad boys” and accepts the inevitable chaos that comes with them. She has no compunctions about lying her way into a job, and little sense of responsibility when she gets it. At the very start of the book, a journalist even suggests she’s a psychopath.

The author of a string of successful thrillers and creator of the BBC drama The Cry, starring Jenna Coleman, Helen FitzGerald upped sticks, as Lou does here, from Australia to Scotland, and she draws on her subsequent experience as a criminal-justice social worker to bring a sense of authenticity and convincing background detail to this quirky, engaging and often frightening novel.

When her benefactor terminates their relationship, Lou casts around for some other way to support herself. Having always had a romantic notion of Scotland, she applies for a job as a night warden in a halfway house in Edinburgh, where serious offenders live after being released from prison to ease their transition back into the general population.

Jenna Coleman and Ewen Leslie starred in The Cry, scenes from which were filmed in Arrochar (Image: free)

Somehow, she passes the interview and flies over at Festival-time, staying in the Airbnb of her chatty cousin Becks, who is starring in the critically acclaimed Plath! The Musical and whose flat is packed with assorted Fringe performers. In no time at all, she has hooked up with a charming, well-off man who, like her, has a taste for sex al fresco.

It all looks very dicey from the start. The halfway house is clearly mismanaged, the boss prioritising her inappropriate friendship with one of the ex-con’s wives over her duties. Lou has to stay overnight in a building full of sex offenders, drug dealers and murderers, including someone she wasn’t expecting to see, and whose presence immediately compromises any objectivity and professionalism she might have been intending to bring to the job – which isn’t much, as she’s been far more concerned with planning city breaks to Rome and Paris in her time off.

READ MORE: The Last Murder at the End of the World, by Stuart Turton

Over the course of the next week or so, Lou is shown to be completely out of her depth, the situation coming to a head in a life-threatening ordeal which has largely been brought about by her own inexperience, recklessness and a misplaced trust that she will somehow muddle through in the end.

Through some nifty character work, FitzGerald does get us on Lou’s side – mainly because of her flaws rather than despite them – helped along by her protagonist’s self-deprecating commentary and a rich seam of dark humour. The resident who makes unconvincing suicide attempts at the same time every night, and the job reference from the sugar daddy’s long-suffering wife recommending her for “demeaning care tasks in a dangerous setting” (explained away by Lou as English not being the lady’s first language) are notable highlights.

The ordeal this has all been leading up to, as Lou faces her first night locked in with a group of ex-cons pursuing their own agendas, pays off all the threads FitzGerald has been setting up in a terrifying and climactic fashion. It’s an offbeat, character-driven thriller that’s hard to resist.