© PA Images / Lionel Cironneau/AP
The actor has joined the cast of Arnaud Desplechin's non-fiction adaptation, reports Deadline.
The film is based on Psychotherapy Of A Plains Indian by acclaimed ethnologist and psychologist Georges Devereux.
The 1951 book centres around a Native American soldier - identified under the alias Jimmy Picard - who was troubled by psychosomatic illnesses following his return from World War II.
Del Toro will star as Picard, who develops a friendship with Devereux (Mathieu Amalric).
Gina McKee will also feature in the film.
Del Toro will next be seen in Oliver Stone's Savages. He recently joined the cast of Agent: Century 21 alongside Cameron Diaz.
AKA Jimmy Picard will begin shooting in Michigan next week.
