It's been a while since I read an action mystery novel as good as this one. Most of what I seem to read is good, but in a kind of enjoyably bad way. This one, in comparison, is good, and well-written, even if it still rests on the sort of slightly tenuous, co-opted science all the others do too.

Honestly, it maybe didn't start so well as it might have. To give some scientific background, the author starts with a few facts, one of which states that, on receiving an injection of stem cells, ageing mice perform better on the Morris water maze, a "test of cognitive function". My main issue with this statement is that the Morris water maze is not a test of generalised cognitive function. It tests a specific cognitive function, that of spatial working memory. But that's just me being very picky (it's what 8 weeks worth of Behavioural Neuroscience lectures do for you). The good news is, all of the facts that the author presents at the beginning are based on actual research papers (albeit ones which take a bit of digging to find). The point at which this research translates to humans is a little weaker. It's just assumed that because the stem cells have this effect on mice, they would have the same effect on humans. Which is a viable hypothesis to make, when you have no reason to think otherwise, but stem cells in mice are only shown to make their muscles heal quicker, and grow bigger, not necessarily turn them into supermice. But, obviously, if you're going to read and enjoy a book like this, you have to take on trust the science.

Besides the science, which I will always pick apart in books (I can't help it), there was only one small problem I had with this. Every now and then, a character will make a bigoted or offensive sounding remark. Maybe it had a point to it to the author, but that point is never made clear in the narrative, so sometimes you end up being jarred out of the story for a moment.

Otherwise, I loved this book. It's based on the past relationship between two brothers, and the remaining one's desire for revenge on the people who killed his brother. The mystery of what actually happened unfolds gradually, and it's definitely compelling. I pretty much started and finished this book within a few hours, it was that good.

And the writing is definitely a step above a lot of books of this genre. It's also not just explosions for the sake of plot, either. It's more on the mystery end of an action mystery, but with enough action and fighting to pick up the pace of it where necessary.

Even though it's so good, it's kind of disappointing there's only one female character in the whole book. And I did love her, but she didn't really do all that much.