Booze? Check. Hot girls and guys? Check. A camera crew on hand to document scripted scenarios? Check.

All ingredients were there for a fun daytime beach bash for the cast of The Hills as they filmed a party scene in Malibu yesterday (September 3).

BFFs and brothers in douchebaggery Brody Jenner and Frankie Delgado could be seen partying like a couple of college kids (sans the college degrees) as pounded back Mickey’s of malt liquor and cans of Bud Light.

Holly Montag, Kristin Cavallari, Lo Bosworth and Stephanie Pratt, meanwhile, played it ladylike by sipping on bottled water and nibbling on cut fruit. For her part, Lo has embodied castoff Lauren Conrad’s identity — strapless white summer dress, aviator sunglasses et al.

And while Holly kept things on the straight and narrow, it appears she needs help — in the form of rehab!

In a new teaser out for season five of the show, which premieres on September 29, resident married couple Heidi Montag and Spencer Pratt discuss confronting her about her drinking. “I think Holly might need to go to rehab,” says concerned sister Holly. “I want to help [her] however we can.”