Struggling to give her son a happy life in Chicago, single mother Karen Barclay scrapes together her meager earnings to purchase a popular talking doll as a birthday gift for her six-year-old son, Andy. Unbeknownst to her, the doll is imbued with the soul of a deceased serial killer, Charles Lee Ray, who transferred his consciousness into the toy through a voodoo ritual to evade death. After Andy receives his new toy, which he names Chucky, a series of horrifying events begins to unfold around the pair, suggesting that the doll may not be as innocent as it appears.

As mysterious and violent occurrences pile up, Andy insists that Chucky is responsible, claiming that the doll has come alive and speaks to him. Met with disbelief, Andy finds himself alone as he tries to convince his mother and the investigating detective, Mike Norris, of the truth. Karen, though initially skeptical, gradually begins to notice eerie anomalies surrounding Chucky. When she discovers that the doll is operating without batteries, her skepticism turns into fear, prompting her to investigate further. She soon unearths the unsavory past of Charles Lee Ray and the possibility that Andy's claims hold truth, leading her on a perilous quest to stop the malevolent force contained within the seemingly benign toy.