Capras Delusion, named after Joseph Capgras, a French psychiatrist who was fascinated by the illusion of doubles, is a debilitating mental disorder in which one believes that the people around them have been replaced by imposters. This is one of the most fascinating anxiety disorders to date. People suffering from this severe mental disorder believe that these imposters are usually thought to be planning to harm the sufferer. In one case, a 74-year old woman with Capgras Delusion began to believe that her husband had been replaced with an identical looking imposter who was out to hurt her.