‘Soo-ah’ spends hellish days everyday due to dating violence of her live-in boyfriend, ‘Hyun-woo’. ‘Anuat’, a man full of mystery, stays by the side of her. Soo-ah goes on a trip to an island with her only friends ‘Yoon-mi’ and Hyun-woo to celebrate her 25th birthday. On the night of the full moon, Anuat follows the footsteps of Soo-ah and encounters evil spirits surrounding her.