The sixth and penultimate book in the #1 New York Times bestselling I Am Number Four series! For years the Garde have fought the Mogadorians in secret, but now the invasion has begun.

John is on the front lines in New York City. The odds may be stacked against him, but his best friend, Sam, has inexplicably developed a Legacy despite being human—and he isn't the only one. As the pair tracks down Five and Nine amidst the chaos, they

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In the year 2030, six teens who have been modified to look like the aliens who are battling for control of Earth go behind enemy lines and discover a shocking, secret alien project

In Tokyo, fifteen-year-old Daniel X faces two of the most dangerous aliens on the planet, who are plotting to use video games to control children and turn them into an army of doom

The enemy is Other. The enemy is us. They're down here, they're up there, they're nowhere. They want the Earth, they want us to have it. They came to wipe us out, they came to save us. But beneath these riddles lies one truth: Cassie has been betrayed. So has Ringer. Zombie. Nugget. And all 7.5 billion people who used to live on our planet. Betrayed first by the Others, and now by ourselves. In these last days, Earth's remaining survivors will need...

"High school senior Cara Sweeney gets more than she bargained for when she agrees to participate in earth's first intergalactic high school exchange program"--

Bob helps a talking rock return to the planet Kal-dor

In 2041 on Moon Base Alpha, thirteen-year-old Dash must solve the mystery of how Lars was poisoned before the base loses oxygen, forcing the colonists to return to Earth.--Provided by publisher.

The Mogadorian invasion has come to Earth, and they have all but won the battle for our planet. Their warships loom over our most populous cities--like New York City, Tokyo, Moscow, Beijing, and New Delhi--and no army will risk making a move against them. The Garde are all that stand in their way . . . but they are no longer alone in this fight. Human teens from across the globe, like John Smiths best friend, Sam Goode, have begun to develop Legacies...

When aliens come to Earth on an interplanetary trade mission, sixth-grader Tim makes friends with the ambassador's son and together they uncover a plot to sabotage the mission

Fourth-grader Zack McGee's life is turned upside-down when Amp, a tiny alien, crash-lands in his bedroom, then causes trouble at school while trying to get parts to repair his spaceship.