Rod Serling: What you're witnessing is the curtain-raiser to a most extraordinary play; to wit, the signing of a pact, the commencement of a project. The play itself will be performed almost entirely offstage. The final scenes are to be enacted a decade hence and with a different cast. The main character of these final scenes is Ilse, the daughter of Professor and Mrs. Nielsen, age two. At the moment she lies sleeping in her crib, unaware of the singular drama in which she is to be involved. Ten years from this moment, Ilse Nielsen is to know the desolating terror of living simultaneously in the world and in the Twilight Zone.
Ilse Nielsen is a bright young girl, but thanks to severe neglect from her shut-in parents, she cannot speak.
At least, that's what Cora and Harry Wheeler think.
Ilse is part of a certain scientific project, wherein a group of scientists dedicate themselves to bringing back humanity's latent ability of Telepathy. However, when a fire breaks out and her parents perish, she needs to enter a world that communicates mainly in spoken word - and hearing words, to her, is a cacophonous, confusing thing after her isolation with her parents.
This episode contains examples of the following tropes:
- Adaptation Deviation: In the short story by Richard Matheson, Proessor Werner tells the Wheelers about the telepathic experiment to which Paal Nielsen and other children were subjected by their parents. In the television adaptation, he keeps it a secret.
- Dutch Angle: Several such shots are used when Miss Frank tries to force Ilse into saying her name in front of her class for the first time.
- First Day of School Episode: The Wheelers enroll Ilse in an actual school, but a lot of factors make it very unpleasant for her.
- Gender Flip: In the short story, the telepathic child is a boy named Paal Nielsen while the Wheelers lost their son David. In the television adaptation, the child is a girl named Ilse while the Wheelers lost their daughter Sally.
- Guinea Pig Family: Ilse's parents Holger and Fanny made her the subject of an experiment from the time that she was born: to induce telepathic ability in her by never speaking to her. Three other German couples, the Werners, the Elkenbergs and the Kalders, did the same thing with their children. All of their attempts were successful, with Ilse being the most powerful telepath of the group.
- No Antagonist: Although our two protagonists start out against each other, both have noble goals and biases of their past. Cora helps out the orphan of a tragedy, but sees all too much of her own daughter in her. Ilse wants to unite with a would-be family, but thanks to her sheltered upbringing, she literally and figuratively can't recognize Cora's words of motherly love.
- Outliving One's Offspring: The Wheelers' daughter Sally drowned at some point before Ilsa came to live with them.
- Replacement Goldfish: We quickly learn, through Ilse's mind-reading, that Cora's beloved daughter Sally died in an accident while swimming. All of Cora's attempts to help Ilse are filtered through this loss, but it's only brought up once or twice by the story.
- Time Skip: The prologue takes place in 1953 while the remainder of the episode takes place in 1963.
- Telepathy: The main conceit of the story is explained at the beginning: Humanity communicated concepts this way before language came about, rather than with miscellaneous mundane sounds and gestures. Speech largely overwrites it, but with severe training, telepathy can be learned like any other language or talent. Interestingly, the talent also provides the ability to see things remotely, such as when Ilse remotely scans the wreckage of her home.
- Translation Convention: With the way Ilse reacts to spoken word, it's assumed that the thoughts we hear are full sentences and/or discrete images for our convenience. Anything Ilse doesn't understand, when her point of view is shown, is played in multiple slightly out of sync, to help the audience understand the sheer dissonance she feels.
Rod Serling: It has been noted in a book of proven wisdom that perfect love casteth out fear. While it's unlikely that this observation was meant to include that specific fear which follows the loss of extrasensory perception, the principle remains, as always, beautifully intact. Case in point, that of Ilse Nielsen, former resident of the Twilight Zone.