When a spaceship lands in the small town of Vern Hollow in 1956, juvenile delinquent Jack Creedle and prim, studious Isadora Shumway form an unexpected alliance as they try to keep a group of extraterrestrials from stealing eccentric Uncle Bud's space travel machine.
In 2017, human-eating aliens have kidnapped two scientists who might cure the disease that is destroying them, and twelve-year-old William Aitkin, his elderly, ailing Uncle Maynard, and the scientists' daughter, Sophie, set out to rescue them.
Sixth-grader Simon Bloom finds a book that enables him to control the laws of physics; but when two thugs come after him, he needs the formulas in the book to save himself.
While visiting Dizzyland near Los Angeles, Klatu, Lek, and Ploo, the three alien siblings from the planet Loogl, find a fuzzy little alien named Mu in the sideshow zoo of the amusement park and decide to set it free.