It's halloween night and seeing little green men equipped with a flying saucer, head antennae and death-ray guns arouses little attention in Big Bean, Illinois in this comedy-adventure. However, on this particular night of tricks and treats, a ghastly cosmic blooper occurs when a group of real Martians intercepts the radio signal from a 50th anniversary re-broadcast of orson welles' famed dramatization "War of the Worlds," and they misinterpret the classic program to be their cue to attack Big Bean and the whole planet earth. Fortunately for the Martians and Earthlings alike -- 10-year-old Kathy Hoxly is "E.T." savvy. With the help of her new friend Brian, her father Sam, who happens to be the town's new sheriff, and old man Wrenchmuller, she rescues the pint-size invaders from a frenzied posse of townfolk, saves the earth from the aliens' blitz, and helps blast the bantam-weight visitors back to their astral cosmos.