Box Therapy

A worker is shown into a dingy office and left on his own. On the floor in the middle of the room is large cardboard box. He is strangely drawn to it. He looks inside. He climbs in and disappears. A few seconds later he emerges from a stationary cupboard. To his horror, he sees himself a few seconds before. To try and set things right he climbs back through the box. Now there are three. Then four. Then five. All with different, extreme personality traits. But where will it end?