On the brink of perfecting his state-of-the-art matter-shrinking machine, the suburban paterfamilias and indefatigable inventor, Professor Wayne Szalinski, realizes that his device truly works, when it zaps both his kids and next-door neighbors' sons. Now, to return to the relative safety of their home while being reduced to a mere quarter-inch size, they must venture out into the dense and perilous landscapes of their now-immense backyard: a hostile environment where nearly everything spells trouble. Can they exit the green maze of grass in one piece?