When it came out 15 years ago, on June 22, 2001, "The Fast and the Furious" seemed like just a 1950s exploitation movie with a bigger budget. Little did anyone imagine that the drag-race drama would turn into an enormous franchise that has earned $3.9 billion to date and spawned six sequels, with at least three more on the way.

As popular as the first "Fast" was -- it earned $145 million in North America and a total of $207 million worldwide -- there's plenty you may not know about how the film came to be. Here are a few tidbits of behind-the-scenes trivia, doled out a quarter-mile at a time.
1. In 1998, reporter Ken Li began writing a series of articles about 30-year-old Dominican street racer Rafael Estevez, first in the New York Daily News, then in Vibe magazine. Director Rob Cohen claimed he was inspired to make the film by reading one of those articles, entitled "Racer X" (for which Universal bought the film rights and adapted into the "Fast" screenplay), as well as by attending an actual illegal street race.

2. The title was licensed from B-movie legend Roger Corman. His 1955 film, "The Fast and the Furious," was about a wrongly-convicted man who escapes from prison and takes up with a gang of illegal street racers. Of course, Corman produced his movie for just $66,000, while Cohen's cost $38 million.

3. While making "The Skulls" for Cohen and producer Neal H. Moritz, Paul Walker mentioned that he'd love to play an undercover cop one day. He didn't know at the time that Cohen and Moritz were developing just such a project.

4. In his college days, Vin Diesel recalled, he had a Suzuki GSX-R sport bike that he would tear along on the highways of Queens, N.Y. But by the time he first played Dominic Toretto in "Fast" at age 33, he admitted, "I'm an SUV kind of guy."
5. Michelle Rodriguez's role of Letty (above) wasn't part of the original script, but the filmmakers created it for her after seeing her breakthrough performance in the indie boxing drama "Girlfight."

6. Neither Jersey girl Rodriguez nor Manhattan-raised Jordana Brewster (Mia) had much driving experience before they made the film; in fact, Brewster (then 20) didn't have a driver's license or even know how to drive. Both actresses had to learn some stunt-driving moves, including slides and sideways turns, for the movie. By the end of the shoot, newly-minted car enthusiast Rodriguez was complaining of the filmmakers, "They wouldn't let us drive faster than 80 miles per hour!"
7. Seen in the movie are some 150 actual street racers, along with their custom cars. They were easy to recruit, recalled transportation coordinator David Marder. "Every one of these kids have monitors hooked up in their cars, where they play video games and use the Internet," he said. "We just put out the word, and they appeared!"

8. The unique circular Beverly Hills house that the police use as their sting headquarters is said in the film to be the home Eddie Fisher built for Elizabeth Taylor. Sadly, that's not true; it wasn't built until 1963, when Taylor had left Fisher for Richard Burton. Less juicy trivia: it's the same house where Walter Matthau's screenwriter character lived in the 2000 Nora Ephron movie "Hanging Up."
9. Moritz and Cohen both have cameos in the film. That's Moritz as the driver of the black Ferrari who races Brian (Walker). And that's Cohen (above) as the pizza delivery man blocked by the first race.

10. Today, Rafael Estevez, the inspiration for the whole franchise, runs a garage in Queens. Journalist Li says Estevez eventually got compensation from Universal for his role as the franchise's catalyst.