Fisher had known Luke as a young actor working at the Sony Pictures gift shop while he was writing the screenplay. Fisher encouraged Luke to try out for the part. An audition with casting director Robi Reed-Humes went well enough that Luke was called in to meet with Washington. Washington was impressed with Luke's audition and asked that he personally deliver the good news. Washington (aware that he was working with an unknown) stated that he wanted to give a younger generation of black actors their chance to come alive on-screen. To prepare the cast, Washington required each actor to know his/her character's history and story inside out before coming to the set. This mandate included everyone from Luke in the title role to key cast members like Vernée Watson Johnson, who plays Fisher's long-lost Aunt Annette, Novella Nelson in the role of Fisher's foster mother, Mrs. Tate, Viola Davis as Fisher's mother, newcomer De'Angelo K. Wilson, seen opposite rapper Eminem in "8 Mile", as the grown-up Jesse, Malcolm David Kelley as the young Antwone, and Corey Hodges as the teenage Antwone. Washington repeatedly told the cast and crew “We’re doing it for Antwone.”