All of Me is a 1984 fantasy comedy film directed by Carl Reiner and starring Steve Martin and Lily Tomlin. This film is based on the novel Me Two by Edwin Davis.
Having discovered she is dying, Edwina has enlisted the aid of a cultureshocked mystic named Prahka Lasa Richard Libertini, who has mastered the secret of transferring human souls. She has made an arrangement with Terry Hoskins Victoria Tennant, a beautiful young woman. Edwina wants her own soul placed in Terrys vacated body so that she can finally experience youth and health. Roger is to change Edwinas will so that Terry, her future self, is her sole beneficiary. Roger, unsurprisingly, believes the whole plan is bananas.Edwina dies at the law office. The soultransfer works, but the vase temporarily holding her soul falls out the window and hits Roger. Roger ends up with Edwinas soul sharing his body. She has control over the right side of his body and he the left. She causes him to lose both his girlfriend and his job. Besides being able to hear her thoughts, Roger talks to Edwinas image that appears in mirrors and other reflective surfaces. Their relationship gradually warms up, but both of them want Edwina out of his body. Terry, meanwhile, is shocked to learn that the soultransference really works, as she only agreed to it to get Edwinas fortune. Terry tries to prevent Roger from reaching the holy man, but when he does, she refuses to cooperate. ........
Source: Wikipedia