At the end of summer, a 17-year-old girl eagerly anticipates a family trip to her dad’s friend’s lakeside cottage before school resumes. She's especially excited to spend time with her brother Dillon, a college wrestler, and her sister Kate, an aspiring surgeon, as they are usually away at school. Their parents, who own a thriving wine business, have planned this vacation to reconnect as a family. The picturesque setting includes jet-skis, a boat, a floating dock, and hiking trails, making it an ideal getaway. Two days into their stay, the siblings embark on a long hike, during which they hear mysterious footsteps. Believing it to be their parents playing a trick, they dismiss their unease. Later, a message from their mom reveals she and their dad had unexpected visitors, a friendly couple living nearby. The next morning, their parents are missing, with only a cryptic selfie from the waterfall as a clue. As the day wears on and no further contact is made, the siblings grow increasingly worried. Dillon and Kate's visit to the neighbors raises further suspicion due to the couple's odd behavior. They contact the police, who find evidence of a struggle near the waterfall and discover that the couple is not who they claimed to be—the real owners are missing. A police search leads to the father’s rescue from the neighbors’ basement. He recounts the horrifying ordeal: he and his wife were attacked, and while he was overpowered, his wife was abducted and ultimately murdered. The couple, along with their son, had a history of violence and had taken over the cottage after killing the original owners. In the aftermath, the couple is sentenced to life in prison, and their son is committed to a mental facility. The family is left to mourn their loss. Five years later, the narrator reflects on the enduring impact of their mother’s tragic death.