Special offer: this audiobook is free until 10am, 3rd October 2019, for Audible UK members with an active subscription.

The Sisters, Cormac Reilly Series, Book 0.5 by Dervla McTiernan is a prequel novella to the acclaimed Irish detective novels. Following the nascent careers of Aifric and Carrie as they try to find their footing as a barrister and police constable, respectively, this book offers us a glimpse into the Ryan sisters' early lives.

Audible Summary: "Carrie, a young Garda shares a studio apartment in Dublin with her recently qualified defence barrister sister Aifric. When Aifric receives a case where a young man has been arrested and charged with the murder of his girlfriend, she decides that he is innocent, and tries to enlist Carrie to help her prove it.

Set a decade prior to Dervla McTiernan’s best-selling detective story The Ruin, The Sisters sets the scene for the trio of books that follow."

I wasn't familiar with McTiernan's books so had not listened to any of the Cormac Reilly series, but couldn't resist giving this free prequel a try. It took a few minutes to warm to the sisters but once I did I found Carrie's story, in particular, compelling and immersive. The two dedicated, ambitious young women faced similar challenges but often found that their careers pulled them in different directions, though in the end they proved to be a good team.

I'd happily listen to other stories about Carrie and Aifric, though neither appears to take the lead in the series that follows this prequel. I understand that they do feature in the series, and it will be interesting to see how they fare when their lives fast-forward ten years in The Ruin.

The narrator, Aoife McMahon, does a grand job with the array of regional accents and characters of all ages and genders. Making the sisters easily distinguishable and and helping emphasise the differences in their characters helped ease me into the story and begin to feel like I knew them. Knowing that she also narrates the full-length novels in the series will encourage me to listen to those, too.

I'd recommend this story to anyone who enjoys crime fiction, especially while it is free to try.