According to Gary Oldman, very little was written about Oswald in the script. Stone gave him several plane tickets, a list of contacts, and told him to do his own research. Oldman met with Oswald's wife, Marina, and her two daughters to prepare for the role. Beata Poźniak studied 26 volumes of the Warren Report and spent time living with Marina Oswald. Since the script contained few lines for the Oswalds, Poźniak interviewed acquaintances of the Oswalds in order to improvise her scenes with Gary Oldman.