This story tells us about young Henry (Jack Nance) living his strange and creepy life full of anxiety. He doesn't feel safe; instead, he feels nothing but terrifying and permanent psychic tension, probably because of the immense amount of changes in both Henry's inner world and on the outside.
Henry's girlfriend, Mary (Charlotte Stewart) gave birth to a baby that looks more like a disgusting creature that looks like a tadpole or a rotten worm. Henry is irritated by this creature as he knows that it is his own flesh and blood. He watches nightmares come to life imagining his head severed and replaced with a tadpole child's head: the little boy finds Henry's head and brings it to the pencil factory to melt it into rubber.
Apart from the feeling of dreadful, unexplainable anxiety, the movie is filled with subtle sexual motifs, which also refer to the body horror genre. David Lynch, the director, shows a scene with a family dinner, wherein Henry's father-in-law cuts the chicken, and the pulsating blood flow comes out covering the table; the scene is accompanied by Mary's orgasmic noises. This image showcases Henry's deviant fear of sexual contacts.
Henry's head, severed and later remelted into rubber, is not the most bizarre body horror part in Eraserhead. David Lynch introduces his body horror part with the scene in which a man with scorched and scarred skin, referred to in the credits as 'Man In the Planet', depicts the main idea. In the distant galactic space on an obscure planet, he sits in a room full of levers. This Man thoughtfully gazes into a broken window and pulls down the levers. Henry, the protagonist, watches the actions of the Man while thinking about surrealistic images – a stretched white strap that falls into Earth's core. This strap brings life onto the Earth's surface, causing the appearance of the primordial soup; in such a way the director draws an analogy between the Man, a great entity that rules the world, and the source of life. In this scene, Lynch also shows Henry's fear, as if his character treats life as eternal suffering and disdains the things that lie in the nature of a human being. For example, the possibility of giving birth to another being. Here, David Lynch touches upon an issue of eternal man's role in human development.