Thirteen-year-old Ike Pressure is used to moving around and starting over. He's an Army brat—and no, that's not an insult, he'll be the first to tell you. He's proud of his mom, who's a U.S. Army Specialist, and he's used to being the new kid at school.

But when Eesha Webb and her family arrive in Mercury, Nevada, the location of the latest base the Pressures call home, everything changes. The Webbs are old family friends, and the grown-ups all expect Ike and Eesha to be instant besties, just like when they were little. Ike doubts someone as outgoing and athletic as Eesha would want to hang out with him, and he's not so sure he wants to be stuck with her, either. The reunion is . . . awkward, to say the least. The truth is, they have absolutely nothing in common.

Nothing . . . except for the fact that neither of them have any idea what their parents actually do on the base, even though they've asked. It's clear something top secret is happening there, but what could it be? Eesha is convinced it has to do with aliens, but Ike is skeptical—until a terrifying run-in with some Men in Black changes his mind. What the kids don't know is that the stakes are actually much higher than alien encounters. Ike's mom is in danger—and along with her, a mission to avert their planet from environmental disaster. Will Ike and Eesha be able to get over their differences and work together to unravel the secrets of Project Mercury and save Ike's mom before it's too late?