'There's something in the sky... something terrible!'

On the night of the great storm, a mysterious new planet suddently appears in the sky. Orbiting the sun between Mercury and Venus, the huge blue-grey sphere has scientists baffled as probes reveal its surface to be flat and bare and its interior liquid.

Eleven-year-old Orville, absorbed in witing for his favourite pigeon to hatch her first eggs, is the first to suspect the true nature of the planet. But will anyone listen to his theory? And, if they do, can they avert disaster? For if Orville is right, the world is doomed . . .