Cars is the first Pixar movie to be released since the studio was acquired by Disney, but it’s a watershed moment for the studio for another, more important reason — it marks their first significant departure from the basic premise of their first six full-length features.

From Toy Story (1995) to The Incredibles (2004), Pixar films have always been set in our world. Each plot unfolds in a contemporary American universe, inhabited by human beings. Each of these films explores a part of this world unseen in everyday life: Toy Story and Toy Story 2 imagine our toys coming to life whenever our backs our turned, A Bug’s Life‘s drama occurs on a scale too small for our eyes to perceive, Monsters Inc. takes place in a universe that parallels and intersects with our own, Finding Nemo takes place under water, and The Incredibles fleshes out the secret lives of super heroes that walk amongst us.

In Cars, for the first time, human beings are absent. Except, of course, they're not. Here is a world in which the rock formations of the American southwest resemble tailfins, in which "cows" are tractors, and in which even the bugs are miniature Volkswagens with wings. But where did these cars come from? What God wrought these creatures in His (or Her) own image?

In one telling scene, Radiator Springs' oldest resident Lizzie (Katherine Helmond) gestures towards a picture of her husband, the town's founder Stanley (like Lizzie, a Model T Ford). This begs a question: what where Stanley's forefathers? Horses? As in last year's Robots, human beings might be absent from this world, but their presence looms over it hauntingly.

The first six Pixar films are effective at fueling young (and young at heart) imaginations because they operate in much the same way. They make sense of the wider, unfamiliar world by imposing a child's understanding of human society on inanimate objects, animals, and nightmares. They take lessons from the World I Understand and apply them to the World I Don't.

And this is why these films are so magical: they reinforce a child's natural inclination to play make believe, compliment a childlike sense of wonder. Cars, though, is a bird of a different feather. Unlike its predecessors it entirely reimagines our world, and instead of making some part of it seem more real, more familiar it instead creates a strange, alien, and even disturbing universe of its own.

Much has been made of Pixar's decision to buck the tradition of equating an automobile's headlights with its eyes and to locate them on the windshield instead. The problem with this approach to anthropomorphizing the characters is typical of a problem with the film as a whole.

The headlights are typically used as eyes because the front of a car resembles a human face. By downplaying this similarity the animators are accentuating the differences between these car-creatures and the vehicles that we drive in our own world, just as re-landscaping desert plateaus emphasizes the difference between the geography of the world in the film and the corresponding area in our own.