ALF tries to escape from the hospital but ends up stuck in an elevator with a woman in labor. After helping the woman to give birth, ALF pretends to be a toy and the cabin owner puts him back in the trunk and they drive away. When the cabin owner is about to jump off a bridge, ALF disguises himself as Santa and convinces the cabin owner to drive back to the cabin, where ALF is reunited with the Tanners.
The Tanner family is an average American family. One day, they discover that they have a visitor. He's small, he's furry, he's arrogant, and he's an alien from the planet Melmac. Unsure what to do, they name him ALF: Alien Life Form. Alf soon decides that as much as he misses his home planet, there's a lot to be said for Earth: the Tanners are willing to concede anything as long as he doesn't announce his presence. Oh yeah, the Tanners also have a cat, which looks rather tasty...