Amber Tamblyn has joined the cast of Spring Breakdown, according to Production Weekly. Amy Poehler, Rachel Dratch and Parker Posey already are cast. Ryan Shiraki will direct Spring Breakdown from a script he developed with Dratch in their first collaboration.

Best of friends and geeks since way back, Amy, Rachel and Becky uncharacteristically decide to take their annual vacation in South Padre for Spring Break, since Becky, who works for Senator Kay Be Rogers, has been assigned to keep an eye on the Senator's allegedly wild daughter, Lindsay (Tamblyn), who's going to be in South Padre for Spring Break with her friends, Truvy and Lydia. When they discover that Lindsay and her friends are even more geeky than they are, everyone decides that this may be the perfect time for everyone to let down their hair and be wild and crazy for once in their lives.

Production is scheduled to begin July 3rd in Los Angeles.