Sean Penn and Robert Pattinson may possibly join Water for Elephants starring Reese Witherspoon. The movie, based on the best-selling book by Sara Gruen, is set during the Great Depression and follows a Cornell University veterinary student who leaves his studies after his parents are killed and joins up with the Benzini Brothers Most Spectacular Show on Earth, working as a vet for the circus.

Richard LaGravenese will adapt the story. Francis Lawrence will direct.