Yet another entry in a long line of critically acclaimed blockbusters for Pixar Animation Studios, Cars tells the story of a cocky race car named Lightning McQueen who learns there’s more to life than racing. Like a lot of Pixar pictures, it also presents a richly detailed world—this one fully populated by cars, completely revolving around cars…while also giving audiences relatable, humanity-laden characters and a poignant plot.

Cars came out more than a decade ago, so a lot of the kids who were mesmerized by the movie in 2006 are now old enough to notice its many other layers—including jokes, references, and, quite frankly, some very weird and disturbing things about the Cars universe.

There’s a lot of adult humor

There aren’t any outright dirty jokes hidden in Cars, but there are a lot of suggestive ones that sailed right over the heads of its five-year-old fans.

For example, Lightning McQueen is a famous race car, and he’s got the groupies to prove it. After his big race at the beginning of the movie, two red cars named Mia and Tia proclaim to be his "biggest fans" and then literally flash him…their headlights. Later, in the movie’s central location of the sleepy town of Radiator Springs, Lightning meets Sally, who has a "tribal" style "pin-striping tattoo" just above her bumper—the Cars equivalent of the "tramp stamp" lower-back tattoo.

In another scene, Lightning barges in on Doc Hudson in his garage—or rather doctor’s office, where he’s got Sheriff elevated to examine his undercarriage. Sheriff asks Lightning if he got "a good look." When Lightning tells Mater that he discovered Doc Hudson was once a three-time winner of the illustrious racing championship, the Piston Cup, Mater incredulously exclaims, "He did what in his cup?" (Say "Piston Cup" out loud if you don’t get it.) There’s even a subtle visual gag or two, such as a sign on the side of a road advertising "Top Down Truckstop," an establishment with "convertible waitresses." (In Cars land, that means they’re topless.)

Character names, and who voices them, were cleverly chosen

The names of characters—and the actors filmmakers hired to play those characters—offer many references that only parents in the know, old movie fans and car enthusiasts would be hip to. For example, Radiator Springs’s old town doctor Doc Hudson is voiced by Hollywood legend Paul Newman, who also raced professionally. Comedian and countercultural icon George Carlin gives voice to Fillmore, a hippie Volkswagen bus—the kind of car countless real hippies drove. (And "Fillmore" bears a similarity to the Fillmore West, a theater in San Francisco where ’60s bands like Jefferson Airplane and the Grateful Dead often played.) Champion race car the King is voiced by Richard Petty, the NASCAR legend known as "The King." Even Tom and Ray Magliozzi, a.k.a. Click and Clack, hosts of the National Public Radio mainstay Car Talk, have cameos as the owners of Rust-eze, the "bumper ointment" company that sponsors Lightning McQueen.

The races are glorified track and field events

As it is in the human world, car racing is a hugely popular sport in Cars. But the cars aren’t driving cars the way humans do in the real world. They’re just running around a track, using their actual bodies. That means auto racing in Cars is essentially a super-fast, super-competitive track and field event. It’s also very high-stakes and highly competitive—cars bump each other and jockey for position at high speeds, leaving each other in the dust or slammed against the wall. This would be like if Carl Lewis or Usain Bolt knocked each other out of the way as they ran. Maybe that violent edge is why the Cars version of "running" is so much more of a popular spectator sport than the real world’s running sports.

The races are brutally violent

Spinouts, collisions, and accidents happen relatively frequently in real-world auto racing events. But the cars are so packed with protective equipment that drivers rarely get hurt. The vehicles take a lot of damage, but fans don’t think too much about it because those cars don’t feel pain.

But they do in Cars. Even the most minor racing incident is more or less a horrific injury. Getting a piece of the car’s body knocked off? That’s like if a human runner lost a body part mid-race. A blown tire? The equivalent of a shattered foot. Viewed this way, the aggressive racing style of the villainous Chick Hicks—which causes the King to roll over multiple times—equates to gladiatorial combat with the intent to harm or kill.

The Pizza Planet truck as you’ve never seen it before

Pixar is well known for lacing its films with well-hidden jokes and Easter eggs, and Cars is no exception. Ever since its first appearance in Toy Story, the beat-up yellow Pizza Planet pizza delivery truck has made an appearance in most every Pixar movie. It makes perfect sense that it would show up in Cars, a movie populated entirely with motorized vehicles. The P.P. truck appears for just a quick flash as part of a crowd scene before one of Lightning McQueen’s big races—and only in Cars does the Pizza Planet delivery truck get to be a living creature with eyeballs and a mouth. (Of course, the implication from there being a pizza delivery truck in Cars is the notion that cars eat pizza.)

The Mack/Lightning McQueen arrangement is a little odd

In creating the Cars world, everything about the human world had to be translated into its car equivalent. Usually, it works—"cow tipping" has been replaced with "tractor tipping," and Flo’s V8 Café serves gas and oil rather than food, for example. However, not everything is a direct corollary, making for some very weird moments.

One big example of this is how Lightning McQueen travels from race to race. As is the case with a real-world race car, he’s hauled around in the back of a specially-built truck. In Cars, it’s presented as something in between a private jet and a limousine, stocked with amenities to ensure maximum comfort for Lightning. But because this is the world of sentient cars, that truck is a living thing. (His name is Mack, as in "Mack Truck.") This means Mack drives down the freeway with Lightning McQueen literally inside of him. This is akin to a private jet pilot keeping his rich clients in his stomach.

Does it take place in an alternate universe…or somewhere else entirely?

Kids can watch Cars on a surface level: cars do stuff, cars learn lessons, cars race. Older people, however, may be left wondering: how and why is the world of Cars this way? It’s about a place almost identical to 21st century Earth, only everything is built for cars rather than humans. But they also enjoy human culture based on real-world things. Radiator Springs is situated on the disused Route 66. Fillmore is mentioned to have lived through the ’60s. Comedian and talk show host "Jay Limo" makes an appearance. They even speak English, except for Guido, who speaks Italian.

So what’s going on here, exactly? Does Cars take place in an alternate dimension in which cars are the dominant species and humans don’t exist, or is it some kind of post-apocalyptic, post-human earth in which cars evolved to a place of sentience and just adopted what was left behind by the now-extinct human race?

There is probably sex in the world of Cars

While it’s unclear how the cars of Cars come into existence, there’s an argument that it’s done biologically—as in a mommy car and a daddy car get together…and a few months later, a brand new car is born. The Cars world is supposed to be just like the human world, after all—and there are strong suggestions that this is what’s happening in Cars. Lightning McQueen and Sally flirt a bunch and are clearly into each other. Mater and Holley Shiftwell become an item in Cars 2. Ramone and Flo of Radiator Springs are married. This all strongly suggests that at least some of these cars bump bumpers on the regular—a biological imperative that probably leads to little cars.