The Overthrow #2: Hatch by Kenneth Oppel

My name is Seth, and the military has imprisoned Petra, Anaya, and me. I understand our hybrid DNA makes us different, but we're the ones who discovered a way to kill the black grass. Ritter runs this secret place, and he's crazy enough to be frightening. There are three types of hybrids: fliers, swimmers, and runners. Ritter is testing our abilities, but it's not hard to imagine he'll want to experiment on us too. A cryptogen in space, Terra, has contacted Anaya telepathically and says she wants to help. She says an army of aliens will be invading soon, and the fliers are the ones leading the attack. I've noticed the other fliers and I have unique abilities, but we aren't the dangerous ones? Esta is pretty intense, but that's only because she's scared, right? I'm not sure who the enemy is anymore. The cryptogens or Ritter? 

You really need to read the first book to fully understand what's going on. This one picks up right where the first book left off. Most of it takes place at the secret military base, although the action moves outdoors later in the book. The tension among the dozens of hybrid kids is the focus of the conflict even though an alien attack is imminent. Terra reveals the fliers control the runners and swimmers on their planet by using a sound weapon unique to their species. This fact plants a seed of distrust among the kids, especially between Seth, Anaya, and Petra. Esta is a new character, and she instigates new problems due to her anger. Petra's character has always been fragile due to her insecurities, and her physical changes are wearing on her nerves. It's a struggle to maintain her humanity while realizing she's become more like the cryptogens. Anaya's communications with Terra create an internal conflict, as she's not sure if the alien can be trusted. She wants to trust Terra, but most everyone else thinks she's being manipulated to give up information. In the end, the hybrid kids aren't sure who can be trusted even though they want to help fight the aliens. Most humans fear and hate them anyhow. I wish the plot moved a little quicker, but I'm curious about what will unfold in the sequel.