Susan Sarandon and Richard Dreyfuss are the latest to join the cast of Tim Blake Nelson’s upcoming comedy thriller “Leaves of Grass,” according to The Hollywood Reporter.

Also starring is Edward Norton, who will play twin brothers. One of them is a highly regarded philosophy professor, while the other spends his time growing marijuana. In a sudden turn of events, the professor must return to his Oklahoma hometown, where he goes against a local drug lord.

Dreyfuss portrays the drug baron, while Sarandon plays the brothers’ mother. Nelson stars as one of the brothers’ best friend. Also on board are Lucy DeVito, Rhea Perlman and Steve Earle.

THR says Nelson wrote the script with Norton in mind, although the actor didn’t show much interest in the project until he finally read the script. Produced on a small budget, “Grass” is scheduled to head into principal photography later this month.

Sarandon was last seen in “Speed Racer.” She recently wrapped filming for Peter Jackson’s upcoming adaptation of “The Lovely Bones.”

As for Dreyfuss, he will next star in Oliver Stone’s George W. Bush biopic “W.” He will also be seen in next year’s Donald Petrie-directed comedy “My Life in Ruins.”