In 1967 Los Angeles, a young widow named Alice Zander works out of her suburban home as a spiritual medium, accompanied by her daughters, 15-year-old Paulina “Lina” and 9-year old Doris. The family is still reeling over the recent death of Roger, Alice’s husband and the kids’ father. At Lina’s suggestion, Alice incorporates a Ouija board into her readings. While trying out the board, she unknowingly contacts a spirit named Marcus that begins to possess Doris. Alice receives a notice that the bank intends to foreclose on their home. Doris contacts the board for help, believing she is communicating with her dead father. The spirit leads her to a secret compartment behind the basement wall containing a pouch of cash. When she gives the money to her mother, the family has an Ouija session, believing they can contact Roger. When the board answers a question only Roger would know the answer to, a thrilled Alice begins believing that they are in contact with her dead husband..
The film was shot digitally, but director and editor Mike Flanagan, in order to add a retro feel to the film, added elements in post-production to give the appearance of a movie shot on film. Those include the ‘cigarette burns’, marks that appear every 20 minutes or so in the upper right corner of the frame, which were used to signal a change of reels for film projected.