The Sanders are a happily married couple. John is a fireman, and Pamela is a makeup artist. To celebrate their 5th wedding anniversary, Pamela's friends Jess, Emy, and Sara suggest a romantic trip. They choose Tarmugli Island, a luxurious beach resort for couples, located in the Bay of Bengal. They bring along their beloved Chihuahua, Daisy. At the resort, they meet a friendly French couple, an Indian couple, and a Chinese couple. Everyone gets along well, enjoying karaoke and a beach party until midnight. The next morning, Mama Anjali, a likable 50-year-old Indian housekeeper, mysteriously disappears. Wendy Armstrong, the British host, assumes Mama Anjali is ill and brings in another maid from her team.
The couples continue to enjoy their stay, sharing stories around a beach fire, eating steaks, and drinking red wine. Suddenly, Wendy and the French couple vanish. The guests start searching the island. John and Pam follow Daisy's barking and discover her barking at three Indian teens with primitive clothes around a fainting Western man. When John approaches, the teens turn with bloody faces—they are eating the Frenchman, Luc. Pam screams, and they flee back to the resort. More cannibals attack the resort, killing and eating the staff. John defends Pam from a young barbarian with a kayak paddle. They escape to Wendy's yacht moored offshore. Aditi, a young Indian maid, Claire, the French woman, and the Chinese couple manage to swim to the yacht, but others fall victim to the cannibals from North Sentinel Island.
The survivors defend the yacht against cannibal attacks while waiting for rescue. Later, the cannibals retreat. Suddenly, John hears Daisy barking. Realizing they left her on the beach, John decides to rescue her alone. Pam tries to stop him, but he promises to return safely with Daisy. John paddles back to the beach, finds Daisy, but alerts the cannibal chief. A deadly chase ensues. John fights and kills the chief, escaping back to the yacht with Daisy. Pam is relieved and hugs them. At dawn, the Indian Navy arrives to rescue them.
