David Fincher recently revealed that it was Ben Affleck's perfect "grin" that made him cast the star for hid upcoming thriller 'Gone Girl.'
During an Interview with Playboy magazine, the 52-year-old director explained that in the film, which is based on the novel of same name by Gillian Flynn, there was a critical scene where the lead character Nick Dunne had to smile in public standing next to a poster of his missing wife, for which he's a suspect, the Hollywood Reporter reported.
Fincher said after Google-stalking the actors a bit, he found that the 'Argo' star, 42, had that ideal "I swear I didn't kill my wife" smile in around 50 of his public shots, which was perfect for depicting a person who was trying to make others around him comfortable but making himself vulnerable to perceptions in the process.