Once I'd started Altered, I couldn't put it down! A thrilling ride featuring a secret government organisation and genetic experiments, it's one of those books that you really enjoy, but once you take a step back you realise a few things didn't really make sense.Altered features four hunky genetically modified boys: Nick, the angry and aggressive one, Cas, the loyal, funny one, Trev, the trustworthy one, and Sam, their fearless leader. They live in Anna's basement, under the care of her father, and Anna regularly helps out with health checks and tests. I'm not entirely convinced that Anna is a believable character - four boys live in glass boxes in her basement, and she doesn't question why they're there? It only occurs to after their breakout that if the boys are part of a generation of super-soldiers, they should be out being tested instead of imprisoned.So they escape, and what follows is basically one long chase scene where five teenagers try to stay one step ahead of a whole agency of determined adults, and manage due to the super skills they have been imbued with. This part is exciting and I literally couldn't bear to be away from the characters and their predicament.However, there are some aspects of the plot that make no sense: at one point our four amazing boys are at a loss to decipher a coded letter. Sam puts all of his considerable knowledge behind it, and comes up with nothing. He even mentions Caesar ciphers. Anna takes one look at the message, seeing it's made up of Xs, Vs and Is, and then needs to look at a clock with Roman numerals to figure it out. Firstly, shouldn't a guy who knows about Caesar ciphers have figured out the ridiculously simple code? Secondly, why on earth did Anna need to look at a clock before realising what was going on?One of the other things I had trouble with in Altered are the 'bad-guys'. They're terribly flat, which is disappointing because Nick, Cas, Trev and Sam are fairly well drawn, but it feels like all the effort went into them, and then every other character suffered for it. I didn't ever fully understand the motivation of the agency -- I mean, I understand the need for super-soldiers, but the way they involved Anna and her family doesn't really make any sense. I'm sure there were other viable ways to ensure Sam's loyalty and obedience.However, there are a lot of things I like about Altered: the focus on genetic engineering is cool, as are the tidbits we get about the alteration program in general. I want to know more about it, but I guess that's coming in future books. I also love the way that the personalities of the four boys play off one another, and off Anna. My favourite things are the lack of love-triangle and the way the romance never completely took over the plot.Altered is a good book, and certainly an admirable début, but it has a few flaws that I hope will be dealt with in the sequel. I want to get to know more about the four boys and uncover the secrets of the agency that created, and see Anna grow into herself. Altered will be enjoyed by readers who enjoy science-fiction-lite, and those looking for an unpredictable, thrilling adventure.You can read more of my reviews at Speculating on SpecFic.