Two couples — Charlie (Dan Stevens) and his wife Michelle (Alison Brie), along with his brother Josh (Jeremy Allen White), and Charlie's business partner Nina (Sheila Vand), who's dating Josh — rent a house on the ocean for a weekend getaway. However, they get a weird vibe from their host Taylor (Toby Huss). When they find a hidden camera in the bathroom, they decide the vacation is over and make plans to leave the next morning.

That night, a series of incidents lead to something far more sinister, as well-kept secrets are exposed. The four come to see each other in a whole new light.