A body swap (also named mind swap, soul swap or brain swap) is a storytelling device seen in a variety of science fiction and supernatural fiction, in which two people (or beings) exchange minds and end up in each other's bodies.
There are different types of body swapping. For non-technology swapping, switches can be caused by magic items such as amulets, heartfelt wishes, or just strange quirks of the universe. The switches typically reverse after the subjects have expanded their world views, gained a new appreciation for each other's troubles by literally "walking in another's shoes" and/or caused sufficient amounts of farce. Notable examples include the books Vice Versa (1882)[1] and Freaky Friday (1972),[2] as well as the film versions of both.
Switches accomplished by technology, exempting gadgets advanced sufficiently to appear as magic, are the fare of mad scientists. Body-swapping devices are usually characterized by a highly experimental status, straps, helmets with many complicated cables that run to a central system and a tendency to direly malfunction before their effects can be reversed. Those without such means may resort to brain transplants. Such experiments can have overtones of horror or erotism.
Body swap is one of the mechanisms of accidental travel in fiction.
In media such as television and film, the device is an opportunity for two actors to temporarily play each other's characters,[3] although in some cases, dialogue is dubbed by the original actors.