Nana and Pop Pop

John and Doris Jamison, otherwise known as Nana and Pop Pop, are the main antagonists in the 2015 horror/comedy film The Visit, which was written by M. Night Shymalan.

The Visit
After Rebecca and Tyler's mother sent them to live with their grandparents for a week, they were advised to never go into the basement because there was mold in there, and that their bedtime was 9:30 PM. One night, Rebecca discovered that Doris was projectile vomiting. When she confronted her grandfather about his wife's  condition, he warned her to not leave her room after 9:30.

Throughout the week, Nana and Pop Pop act even more strange. For example, Nana began to shake violently when Rebecca asked her about what happened on the day her mother left, and they were shown as being very hostile to a woman they had been counseling. They lead the woman away to some unknown place, and she was never seen again. Tyler and Rebecca decide to use a second camera so that they could record any unusual actions that went on downstairs, and Nana finds the camera, and she grabs a knife, and she tries to break into the kids' room.

After they had recorded the footage, they contact their mother, Paula. When she was shown what Doris and John looked like, she reveals that they were imposters. The two siblings try to escape, but the impostors force them to play Yahtzee with them. Rebecca excuses herself from the table, and she goes into the basement. After rummaging through a box in the basement, she finds the corpses of the real John and Doris Jamison, and they were dressed in their mental hospital uniforms, thus implying that the impostors were escaped mental patients.

Pop Pop discovers her, and he locks her in a room with the disturbed Nana. He then started to psychologically torment her younger brother by smearing his face with his dirty diaper. Rebecca manages to stab Doris to death with a glass shard, and she runs into the kitchen and tackles John. When John was starting to get the upper hand, Tyler attacks him and knocks him to the floor. He then proceeded to repeatedly slam the refrigerator door onto the fake John's head, until he was dead.

The film then ends with Paula reuniting with her children.