Films involving either mind transfer, possession, or the complete physical replacement of human bodies and minds with alien or demonic substitutes ("pod people").
Note that Lovecraft all but helped to invent the modern possession story, having written a number of stories involving the bodies of human characters getting possessed by the disembodied spirits of ancient wizards or alien minds projected across time and space into their human hosts.
There is, after all, only a fine line between Lovecraft's descriptions of a human character's body getting "possessed" by aliens or wizards in stories like Shadow Out of Time (fiction) or Thing on the Doorstep (fiction), and what we see in The Exorcist - the only real difference being the superficial trappings of religion in The Exorcist which would only barely be out of place in Lovecraft's atheistic universe....
Trivia: Capgras Delusion is a belief that other people have been replaced with imposters, duplicates, changelings, or doppelgangers. Fregoli delusion is the belief that various people whom the believer meets are actually the same person in disguise. Intermetamorphosis is the belief that people in one's environment swap identities with each other while maintaining the same appearance. Subjective Double Delusion is the belief that there is a doppelgänger or double of him- or herself carrying out independent actions. Mirrored-self misidentification is the belief that one's reflection in a mirror is some other person. Somatoparaphrenia is the delusion where one denies ownership of a limb or an entire side of one's body; Cotard Delusion is the belief that oneself is dead or does not exist; sometimes coupled with the belief that one is putrefying or missing internal organs; Sleep Paralysis disorder (a condition in which the sleeper awakens, unable to move, often accompanied by vivid hallucinations and delusions of strange beings or evil spirits in the room with the sleeper) has symptoms include delusions that one's sleeping body is under attack by evil spirits.
Pages in category "Film:MindTransferDoppelgangers"
The following 69 pages are in this category, out of 69 total.