Amelia, who lost her husband 6 years ago and raised her son Samuel solely in the process, finds a mysterious fairy tale book called Mister Babadook one day in her son’s books. After reading the book, Samuel tells you that you saw Badabook’s monster in his dream. From this day on, mysterious things begin to happen.
As the Amelia book disappears, the mysterious book begins to reappear somewhat. Samuel’s nightmares, on the other hand, will become increasingly violent, which will start to shake Amelia deeply. Could it be that the mysterious Badadook, which started embroidering both Amelia’s and Samuel’s caves?