In the hope that science will find a cure for the genetic mutation that has made him and his three children geniuses while condemning them to gigantism and short lives, Julian "Bean" Delphiki, aka the Giant, takes them into space. Travelling at light speed, however, allows them to be forgotten on Earth, where hundreds of years have passed, and when their ship begins to fail and Bean nears death, the siblings, now six years old, must save themselves.