Echogenesis

I had a lot of gripes with the first half of the book. It read like a play. There was not much narration and the plot was advanced solely via dialogue. The characters are not fleshed out, they are just plot devices, and their copious dialogue is empty too. This section of the book is the reason I can't conscionably give it more than 3 stars overall. 
But after the first plodding, disjoined half was over, the story really came into its own and I'm glad I persevered. The plot become interesting and twisty-turny. It even managed to go out with a bang. 

I will also say the book needs an editor. Grammar errors,  discontinuities of character and plot holes abound. Fair warning if you can't get past that kind of thing. 

I stopped reading when (1) a character believed they were on an alien world because there was no moon in the sky, and other characters didn't point out the flaw in her reasoning, (2) two of the characters suddenly decided to have sex in the nearby forest in the middle of the night and it was blamed on the fact that they were suddenly the equivalent of eighteen years old and their hormones had become super active, and (3) the name of a character suddenly changed to that of another character in the middle of a scene. There were other less problematic things in the writing as well, but the three issues mentioned above were enough to make me stop reading.