Doctor and researcher Guillaume Duchenne de Boulogne became obsessed with smiles. His electrical experiments allowed him to conclude that a truly happy smile is formed not only by the muscles of the mouth but also by those of the eyes. That kind of smile is called a Duchenne smile. Many researchers have suggested that the Duchenne smile indicates spontaneous and genuine emotion since most people cannot contract the orbicularis muscle at will. Duchenne's Smile is a psychological horror thriller that addresses the traumas of those who, in the abandonment of their own mind, can only glimpse at their dark past.