The frigid swells off the coast of Antarctica buffer Team Cousteau's kayaks as they weave through the icy water. They're losing daylight, and at risk of failing their fieldwork assignment. But Cruz Coronado's thoughts are elsewhere. Nebula is closing in, and time is running out. The evasive explorer spy is still out there. And in his gut, Cruz knows his final mission will have deadly consequences. In The Forbidden Island, the electrifying seventh and final book in the Explorer Academy series, Cruz wonders if fortune really does favor the brave. After all, his mother's hologram rejected the latest piece of the cipher, grinding his progress to a dismal halt. On top of that, terrifying truths keep bubbling to the surface. But in a journey that has taken him to all seven continents, Cruz isn't ready to give up, and neither are his closest friends, Lani, Emmett, and Sailor. In fact, Cruz is prepared to risk everything he loves to recover the cell-regeneration formula and continue his mother's legacy. As Cruz follows his path to the most otherworldly destination yet, a final showdown erupts when a familiar face appears, changing his life forever.