Gordon Shumway, last known survivor from the planet Melmac, crash-lands his spaceship into the Tanner family's suburban garage. Willie dubs him "ALF", short for Alien Life Form. After convincing a military officer that they are not harboring a space creature, the Tanners decide to take ALF in as a member of the family.

Six years ago, the space alien, ALF, was on his way back to his new home...When the Alien Task Force finally caught him. Now, the story continues to where the series ended. ALF is now protected by the Alien Task Force, but the leader wants to terminate ALF. So two officers decide to save ALF by taking ALF away from him. But the man the officers took ALF to wants to finally reveal ALF to the world. Which leads him to more danger...