On a trip to the woods, the Hendersons run into the legendary Bigfoot in front of their car. Believing they killed the shaggy giant, George, Nancy and children Sarah and Ernie secretly take him home. However, when Bigfoot wakes up there again, he turns the house completely upside down. There is panic at first before the Hendersons realize the good-natured nature of their furry new roommate, Harry. But when not only the neighbors but also the press and a Bigfoot hunter find out about them, a race against time begins to bring the supposed monster to safety again...