Bardem spent one-and-a-half months in New York City with Arenas's best friend, Lazaro Gomez Carriles, taking two hours a day to study how Arenas walked and talked.
Bardem menjalani satu setengah bulan di New York dengan sahabat Arenas, Lazaro Gomez Carriles, menjalani dua jam sehari untuk mempelajari bagaimana Arenas berjalan dan berbicara.