A moonlit garden becomes the threshold to an impossible universe when George Carter finds Lea, a terrified girl no bigger than a hand, wounded and half-dead with fear. She is a princess from Helos, a hidden world of infinite smallness inside an atom, and her arrival pulls George, his blind sister Alice, and their scientist father into a mystery where science and wonder collide. As Lea learns English, she reveals a civilization of the Heanas, peaceful yet shadowed by jealousy, ambition, and exile. Their greatest threat is Taroh, a disgraced chemist banished to the savage Malobs, who has stolen the secret of a drug that can make living things grow to gigantic size. With that power, he plans to destroy Helos. Lea's own desperate escape, using the drug to outwit danger and cross a shrinking, nightmarish landscape, leaves the Carters stunned—and George determined to find the opposite force: a pellet that shrinks instead of enlarges. When that violet pellet is discovered, George and Lea take it, shrinking together into a world where a garden becomes a wilderness of towering trees, cliffs, and colossal stone. Their journey toward Helos grows ever more perilous, guided by Lea's memory and shadowed by the promise of reunion, as they descend into a dazzling, dangerous adventure where the fate of two worlds hangs in the balance. This edition has been fully restored with modern typesetting, custom cover design.