There are no new plots, in YA as in other fiction, so the challenge is to mix and match and create new flavours. So Revis gives us the female teen protagonist - Ella - only child of two brilliant parents - one dead and the other dying. A benevolent, post-apocalyptic global dictatorship gone bad. Robots - androids - that may or may not be self-aware. Memory and identity. Freedom fighters, now sadly depleted so that there are just four left - Ella plus Jack, Xavier and Julie.
Julie and Xavier are barely sketches - there for the fights and the chases and to give tension to the group - they don't trust Ella, but bow to Jack's judgement. Jack is better drawn and seems to know Ella very well indeed - but she has no recollection of this.
So Ella is searching to understand who she is and where her memories have gone. And who she can trust, if her memories can be tampered with...
Revis cites P K Dick's work as being heavy influences, and I'd agree. There are clear parallels with Blade Runner and Total Recall. (I'm using the film titles as they're better known than the stories on which they're based.)
Everything was going well until the last ten chapters (there are about 80, but fairly short), and I really thought Revis had lost it. I can sort of see why she did what she did - I'd point to Inception, Source Code and Groundhog Day - but it seemed unnecessarily repetitive. Yes, each scene did play out a little differently, and a little bit more was learned about the nature of the enemy at each pass, but given that the enemy was supposed to be in control, they kept on repeating tactics which were clearly doomed to failure - 'This is your last chance, Mr Bond'. As I say, it got very repetitive and I can see the (stereo-)typical YA reader getting bored and frustrated.
So by the last chapter, when it all gets wrapped-up, I was not feeling sympathetic, and knocking off stars right, left and centre. Ella adopts typical superhero morality when meting out punishment to her defeated enemy, acting as both jury and judge.
I re-read the last couple of chapters, a day later, and decided I'd been a bit harsh. Revis' villain is at least shades-of-grey - a victim of end-justifies-the-means thinking. So one of those stars gets re-instated.
Final thought, then - a mostly-comfortable read with interesting ideas woven into the plot. Lots of nods to good adult SF. Add my usual moan about awful computer security in YA novels - I think I ought to write a blog about that - and I'd say that it is on a par with Hunger Games (with which it shares a first person present tense PoV), without being derivative.