In the winter of 1982, a twelve-man research team at a remote Antarctic research station discovers an alien buried in the snow for over 100,000 years. Soon unfrozen, the form-changing creature wreaks havoc, creates terror... and becomes one of them.
Hoping to bring his family closer together and to recreate his childhood vacation for his own kids, a grown up Rusty Griswold takes his wife and their two sons on a cross-country road trip to the coolest theme park in America, Walley World. Needless to say, things don't go quite as planned.
With his wife's disappearance having become the focus of an intense media circus, a man sees the spotlight turned on him when it's suspected that he may not be innocent.