Pixar was on a hot streak. What started as a promising novelty with "Toy Story" had grown into the hottest name in animation -- even overshadowing parent company Disney -- with a run of acclaimed hits "Toy Story 2," "Monsters Inc.," "Finding Nemo" and "The Incredibles." That didn't exactly screech to a halt with "Cars," but the film's reception was enough to make fans realize not every Pixar release would be a winner. The first speed bump came with critics, who gave the film positive reviews overall but noted the lesser quality of story and character workmanship, especially in the wake of "The Incredibles." "Cars" still brought in a highly respectable $244 million at the U.S. box office, but that was less than the four Pixar releases before it. The movie suffered another ding when it lost the Best Animated Feature Film Oscar to "Happy Feet." None of this would've caused much concern coming from any other animation studio, but Pixar wasn't just any other animation studio. Still, they doubled down with a sequel five years later, and the only reason the lackluster "Cars 2" wasn't an even bigger letdown was because "Cars" had already laid the groundwork that Pixar wasn't invincible.

-Geoff Berkshire