Just days after signing on for “The Hangover Part III,” Heather Graham has joined the cast of “Feed the Dog,” an indie comedy (formerly known as “Parental Guidance Suggested”) that will star Selena Gomez.

Tim Garrick is writing directing the CAA-packaged teen laffer, which is based on Ric Browde’s novel “While I’m Dead … Feed the Dog.” Andrew Lazar is producing via his Mad Chance banner.

Nat Wolff and Austin Stowell co-star alongside Dylan McDermott, Elisabeth Shue and Cary Elwes.

Graham will be busy this fall, as she co-stars in Ramin Bahrani’s Venice-and-Toronto-bound drama “At Any Price,” as well as the kinky indie “About Cherry,” which hits theaters Sept. 21 and is currently available to rent on iTunes.

In addition to promoting those pics, she’s set to reprise her role from “The Hangover” in WB’s latest sequel, which starts production next month.Graham is repped by the Gersh Agency and Risa Shapiro of The Schiff Co.