Set in the 1980s, the film follows Samantha Hughes, a broke college student who takes a strange babysitting job to earn money. Despite several red flags, she accepts a gig at a remote Victorian house during a lunar eclipse.

When she arrives, she learns there's no child to babysit—instead, the elderly couple, Mr. and Mrs. Ulman, want her to “watch over” the old woman upstairs. Desperate for cash, she agrees. As the night progresses, Samantha begins to experience terrifying events and realizes she's part of a satanic ritual connected to the eclipse.