It seems that there were joint auditions held sometime in 1975, a fact confirmed by Brian De Palma himself in the making-of documentary film “Acting Carrie.” De Palma said that “George and I were both looking for unknowns so we sat together and basically went through hundreds of boys and girls, looking for the cast for ‘Carrie’ and ‘Star Wars.'” The same documentary also featured an interview with actress P.J. Soles, who played the character of Norma in De Palma’s movie. She said that she walked into a room with both directors and recalled that De Palma was the more animated director of the two. In her words:
“I just remember right away Brian looking at me and I could just sort of tell that he liked me and then George Lucas was just kind of stern-faced and Brian turned to him and said ‘I’ll put this one on my list.'”
At the time, “Star Wars” was considered a minor but well-budgeted project. “Carrie” was made for under $2 million, while “Star Wars” ended up costing about $11 million. As such, many, many actors were eager to take part. Amy Irving, who played Sue in “Carrie,” recalled seeing Lucas in the middle of the room for her audition. She said:
“I had never made a film before and I was doing a production of ‘Romeo and Juliet’ on the stage when this audition came up for ‘Star Wars.’ Everybody in town was going in on this and Brian De Palma was sitting in the corner of all the interviews that George was giving. And he was kind of like making us a little mental note to say ‘Okay, George can only pick so many, you know, I’ll see what’s left.'”