Twisted Nerve

Martin plays catch with his older brother Pete, who has learning difficulties and has been sent to a special boarding school in London by their mother. Their father died years earlier, and their mother has started a new life with her wealthy banker husband. The school's physician believes that Pete cannot be expected to live much longer.

Martin pockets a toy duck while Susan buys a toy in a shop. Two store detectives pull them aside and demand they return to the manager's office, accusing them of conspiring to steal the toy. Susan denies ever having met Martin, leaving the detectives unsure about any real link between them.

Under questioning, Martin presents himself as Georgie and feigns a mental disability. The manager is unconvinced by any link to Georgie and asks for Susan's address; Martin discreetly notes it as Susan offers to pay for the toy.

When Martin returns home, his parents argue about his apparent disinterest in life and the duck incident. In his room, as Georgie, he rocks in a chair, smiles at his reflection, and caresses a stuffed animal, then smashes the photo of his stepfather.

The next day, Susan goes to the library after school, where Martin approaches and Susan recognizes him as Georgie. Martin admits he followed her and returns the toy, then convinces Susan to lend him The Jungle Book.

Martin has a heated dispute with his stepfather, who insists he travel to Australia; Martin refuses and retreats to his room. He stares into the mirror, bare-chested, caresses himself, and notices bodybuilding magazines before smashing the mirror in a fit of frustration.

Martin begins to stage a departure to France but instead shows up at Susan's mother's house dressed as Georgie. Susan and her mother offer him shelter, and he stays with them, hoping Susan will accept him as a lover without revealing his true identity.

One night, Martin steals scissors, leaves the house, and fatally stabs his stepfather after a dinner party. The murder triggers a police investigation and puts Martin on the run.

Days later, Martin accompanies Susan on a swim at a country lake and makes a crude attempt to kiss her, which she rejects. The moment marks a deeper drift between their growing closeness and his dangerous secrecy.

Susan searches Martin's room and finds books about learning difficulties and Know Yourself from Your Handwriting, with signatures that read 'Martin Durnley.' She realises that Martin and Georgie may be the same person after seeing a photo that links the two identities.

Shashee, a hospital worker, discusses split personalities with Susan and confirms that the two identities could explain the case, prompting him to race to the house to help when danger is revealed.

At Susan's house, Martin loses control as he suspects Susan knows the truth. When Susan's neglected mother attempts to sexually arouse Martin, he kills her with a hatchet.

Police burst into Susan's room as Martin fires three times at his reflection in the mirror and is subdued. He is taken away, still insisting that he is Georgie and that he has killed Martin.

Martin is confined in a cell at a mental hospital, ranting about his lost love Susan and the life that might have been with her.