October 28th, 2016 is National Frankenstein Day.

Hollywood portrays him as hulking, green, with rivets sprouting from his neck and stitching twining around his limbs. He burns down buildings, terrorizes towns, and chases after his creator. He was the product of the first mad scientist the world ever knew, the brainchild of Mary Shelley and a dark and stormy night. No, friends, it is not Frankenstein; rather, Frankenstein’s monster.

As with most book-to-movie adaptations, Hollywood amped up the fear factor and created the Frankenstein we know and fear today with the 1931 rendition of the novel. Further spinoffs resulted in the creation of the bumbling lab assistant Igor, who, sadly, makes no appearance in the original film. After enough of these sequels, too, is when people started to refer to the creature as Frankenstein himself, not Dr. Frankenstein’s monster (which, let’s be honest, is a bit of a mouthful).

If you read the actual novel, however, it tells a slightly different tale of a creature unwillingly brought to life by a lonely, grief-stricken scientist, a creature who craves companionship and is afraid of his own reflection. The creature is intelligent and conniving, and Dr. Frankenstein is convinced he is evil. There is a bit of terrorizing and framed murder and village burning, but only after his creator ghosts on him.

For such a dark subject matter, the author doesn’t quite fit the subject profile, especially for the time. When Mary Shelley wrote the novel, she was only 18 years old, and she had two children! Despite all this, she said that this twisted idea came to her in a single inspired moment: “I saw the pale student of unhallowed arts kneeling beside the thing he had put together. I saw the hideous phantasm of a man stretched out, and then, on the working of some powerful engine, show signs of life. … He sleeps; but he is awakened; he opens his eyes; behold, the horrid thing stands at his bedside, opening his curtains and looking on him with yellow, watery, but speculative eyes.”

Mary opened her eyes and realized she’d found her story. “What terrified me will terrify others,” she thought.

It’s a line like this that has inspired horror films to this day.