1. Olivia Wilde was almost cast as Marissa Cooper.
2. When Adam Brody auditioned, Josh Schwartz said he hated him and wanted him to get out.
3. In early drafts of the script, Ryan Atwood was originally going to be Sandy Cohen's illegitimate child.
4. Chad Michael Murray was reportedly offered a part in The O.C., but turned it down for One Tree Hill.
5. The Cohen's pool is actually only four feet deep, which means the actors had to film swimming scenes on their knees.
6. Rachel Bilson was originally only a guest star, but the role of Summer Roberts became so important that they made her a main character.
7. The producers almost didn't use the iconic Phantom Planet song for the intro.
8. Seth was reportedly going to be a part of the popular clique, but the writers decided to make him an outcast.
9. Luke was often called "Abercrombie" in a derogatory way, a joke that refers to his previous job as a model for the retailer.
10. Adam Brody is afraid of boats, and used a stunt double for the sailing scenes.
11. Tate Donovan, who played Jimmy Cooper on the show, voiced Hercules in the film and the animated series, as well as in video game Kingdom Hearts II.
He also dated Jennifer Aniston; the two were briefly engaged.