Scott and Annie Russell, a young couple, move into their dream home in Napa Valley, hoping to start fresh. They purchase the house from Charlie Peck, a seemingly amiable yet eccentric homeowner who is reluctant to leave his family estate. Despite selling the property, Charlie maintains an unsettling presence around the house, showing up unannounced and performing maintenance tasks without permission. His behavior gradually becomes more intrusive, causing Scott to grow increasingly suspicious of his intentions.

As Charlie's visits escalate in frequency and abnormality, the tension between him and the Russells intensifies. Scott starts investigating Charlie's background and uncovers disturbing details about the home's past and the true nature of its previous owner. Annie, meanwhile, becomes more sympathetic to Charlie, leading to conflict between her and Scott. The situation reaches a boiling point as Charlie’s actions become more menacing, threatening the couple’s safety and stability.