Mika and Ellie live in a future behind a wall: Solid concrete topped with high-voltage razor wire and guarded by a battalion of Ghengis Borgs, it was built to keep out the animals, because animals carry the plague. At least that's what Ellie, who was kidnapped as a child, has always been taught. But when she comes to suspect the truth behind her captivity, she's ready to risk exposure to the elements and answer the call of the wild. Listen. Can you hear it? She's strapping on her headset, jumpstarting her Pod Fighter, and—with her capuchin monkey at her back—she's breaking out!

Listen—can you hear it? The explosive sequel to THE ROAR! From a whisper...to a scream! Telepathic twins Mika and Ellie at last are reunited. But if they're ever to free the brainwashed, microchipped child soldiers, they must pretend to play along with the tyrant Mal Gorman's maniacal plan, even as they mind-read his every evil thought. Members of an elite squadron of mutants, the brother and sister have specialized skills that will enable them to steal the top-secret formula for an age-reversing drug developed by rebel scientists on the wild side of The Wall. Juiced by these potent pills, the cadaver-like Gorman foresees a future in which he'll be forever young - released from the machinery that now supports him. Unless, that is, Ellie and Mika have a master plan of their own: to bring the all-powerful Gorman to his knees, and face-to-face with his greatest fear.