Rosa and Eddie are among hundreds of teens applying to NASA's mysterious Interworlds Agency. They're not exactly sure what the top-secret program entails, but they know they want in. Rosa has her brilliant parents' legacies to live up to, and Eddie has nowhere else to go--he's certainly not going to stick around and wait for his violent father to get out of jail. Even if they are selected, they have no idea what lies in store. But first they have to make it through round after round of crazy-competitive testing.

And then something happens that even NASA's scientists couldn't predict...