Former mayor of New York Frank Avellino is dead, hacked to death in his bedroom, a truly savage murder. The police are quickly on the scene, summoned by two 911 calls. His two daughters, Alexandra and Sofia, both called from inside the house – and both accuse the other of committing the crime.

Three months later and the trial begins – the trial of both sisters. Eddie Flynn is defending Sofia and an up and coming lawyer Kate Brooks has wrested control of the defence of Alexandra. Both are convinced of their client’s innocence – but one of them must be mistaken. As the trial progresses, it becomes clear that this is more than a simple case of a sudden outburst of rage – this murder had been a long time in the planning, and it’s quite clear that Frank was not the murderer’s only victim…

OK, a bit of background first. It’s taken me two days to even start reading a book this week. Various things are going on (you’ve probably noticed at least one of them) and my head has been all over the place. In case you’re worried, me and my loved ones are all fine – it’s mostly other stuff. Anyway, I started maybe ten books – some old favourites, some classic, some new, and I’d not make it to the end of the first chapter before my brain was off on some random tangent and I’d put the book down. Needless to say, not being able to settle on a book becomes something of a vicious circle, as that sets me on edge as well, and just makes things worse.

So I thought I’d go for something with an immediate hook – hence Fifty Fifty. Steve Cavanagh’s Eddie Flynn books have a clear central idea – the killer is actually in the jury (Thirteen), the lawyer has a bomb strapped to his back (The Defence), etc – and here he sells convincingly the idea of a trial with two defendants, one of them innocent, one of them guilty. And I was hooked from the first chapter – reading problems over. Hurrah!

What I found interesting is that Cavanagh sets out the clear problem very early – the chapters focus on different points of view, Eddie, Kate and “She”, “She” being the murderer, who conveniently doesn’t name herself. But it is clear that the murderer is indeed one of the two sisters and that only one of the sisters was involved in the murder – so the reader shouldn’t be looking at anything other than which one of the two is the murderer.

The “She” chapters are a bit bonkers actually, as “She” goes around tidying up loose ends that might convict her, one in particular that eventually actually does (although if the reader is looking for that crucial clue, it is a visual one that I don’t think is shared with them until the reveal). There are a few fun bits where “She” reveals something she did with her lawyer, only for the next Eddie and Kate chapters to reveal that they both did that with their clients. There’s a lot of this sort of thing with the author playing narrative games with the reader, with one chilling example being a countdown of sorts with two of the support characters oscillating paragraphs while they answer a late-night knock at the door – needless to say, we’ve just seen “She” heading towards someone’s door…

It’s a really enjoyable book – the central characters are good company, as are their small circles of friends. When something bad happens to one of them, it’s a genuine shock, and while you can guess early on where things will be standing by the end of the book, it’s still a fun ride getting there.

However, I should say that the author does pick a difficult game to play here – which one of two is guilty? – and I’m not sure that many people will be surprised as to the guilty party. It’s hard to pull of surprises with this plot – Paul Halter’s The Seventh Hypothesis and John Rhode’s The Robthorne Mystery are the best examples that I can think of – but it’s a sign of the strength of the book that even though I was sure who the killer was from early on, I didn’t particularly mind when my guess was confirmed.

Overall, this was a really enjoyable read, and exactly what I needed to get my reading back on track, so many thanks to Steve Cavanagh for that.

Fifty Fifty is out now in paperback and ebook.