Aspen Matthews is one of the Blue, a race of humans who live under the water. Except, she's been raised on the surface world, and continues to live in our world, acting as a liaison between the two worlds when possible.
When she finds a member of the Blue, deep under water, and seemingly trapped, she lets him out before she can find out any more about him.
Turns out he wants to burn everything in his path, and hey, they're on the surface. Can Aspen fight off the evil, stay off Twitter, and keep her identity a secret?
Let's see...