Scholar Jules Addison and scavenger Amelia Radcliffe join forces to unravel secrets of a long-extinct civilization, only to discover something that could spell the end of the human race.

Almost seventeen-year-old Alison, who has synesthesia, finds herself in a psychiatric facility accused of killing a classmate whose body cannot be found.

In rural Ohio, friendships and a beautiful girl prove distracting to a fifteen-year-old who has hidden on Earth for ten years waiting to develop the Legacies, or powers, he will need to rejoin the other six surviving Garde members and fight the Mogadorians who destroyed their planet, Lorien. Friendships and a beautiful girl are distracting to a teenager who is hiding on Earth while he waits to develop the powers he will need to rejoin the other six...

In a Spanish convent, seventeen-year-old Marina longs to join forces with her fellow Loriens to prepare for battle with the Mogadorians who destroyed their home planet, while in the United States, John, Six, and Sam elude authorities who think John is a terrorist.

Twelve-year-old Gratuity Tucci has a hard time writing an essay on "The True Meaning of Smekday" due to her complex life after Earth was overtaken by aliens and her mother was kidnapped and taken to Happy Mouse Kingdom in Florida.

Two years after the disappearance of her father, seventeen-year-old Liv and her friend capture an alien in the Iowa countryside, and instead of turning him over to the authorities, they choose a different path.

When Earth receives messages from another world, claiming that they created the planet and are planning to destroy it within a week, three teens are forced to confront the mistakes of their past before they run out of time.

For a school assignment, a boy reluctantly writes a letter to Clunk of the planet Quazar, sending his older sister with it, but as more letters and packages are exchanged, he realizes that having an alien pen pal can be fun.

In a future where alien beings consume technology as a few humans try to preserve it, Strata, her brother, and a friend are separated from their caravan and, with a wonderful robotic horse, must fight their way back.

On the same day Matty Jones's father disappears, Priya, a strange girl appears on his family farm claiming to be awaiting the return of her space ship, driving Matty to start believing in all the things he can't see.