The "Unreliable Narrator" in novels and films

Rating: 8/10 (27 October 2014)

A popular trick in novels is the "Unreliable Narrator." One of the characters tells us everything that happened; but then we discover that character missed important events, or is lying, or is insane. Perhaps another character then tells everything from their point of view; and then we realize the first character was lying. Perhaps the second character is also lying. Etc. This "Unreliable Narrator" technique can make novels very entertaining (especially mysteries.) The problem with films: we usually believe everything we see happening on the screen (unless it's obviously a dream or hallucination.) How can a writer and director and actor show a lie on film? In "Gone Girl," is everything we see and hear true? Or is it possible the director showed us events that didn't happen?