Although frequently portrayed in film and fiction, the often-referenced "body swap" is completely fictional and at this point in time impossible to perform in reality, states The Guardian. No spells to switch bodies have ever been substantiated by science.
Scientists have long wondered if body swaps are possible, but any science to attempt it is, as of 2015, completely unknown. One unsubstantiated theory consisted of an attempt at a brain transplant, which would most likely be unsuccessful in even allowing someone to survive in his original form, let alone survive in another body. In theory, for this to work, one must believe that the mind and body are completely separate entities, known as a Cartesian dualist set-up. The problems that would result from body swapping are unlimited. For example, by switching bodies, memories from one person would presumably be transferred into the other person's body, leaving one person with two full memory sets yet being completely unfamiliar with his new bodily environment.