The Bronze Key is a an obvious middle book in a series. It ends on a big cliffhanger. In the process they discover that keeping secrets is not all that great. Call also learns that if he is not going to bother asking the girl out, somebody else will. The kids now become more comfortable with their school environment, but also realize there is more crazy stuff going on in the world. Like in Harry Potter, the "magic world" is "hidden in plain view" from the real world.
They get to the school and more conflict breaks out. Eventually, Call tells his friends some of the experience with his dad. However, he does not tell the full story, and that makes things even worse. They end up on a big adventure. In the end, they find out more about who he and his father are and they decide not to keep secrets from each other.
Most everybody would love to pass for the "rewards" it entails. Callum Hunt has been told by his dad to stay away from magic, making him one of the rare people that want to fail the trial. Alas, a mage brings him in. He seems to have unbridled power. They want to help him control it. He can interact with other beings such as a "pet" he has. He is told that he may be much more than he thinks he is.
The book ends with a "resolution" to a minor episode. It is pretty clear that there is much more to come in the future books.
