Youngjun's university student who doesn't believe in the supernatural. However, his skepticism is shattered when his younger sister, Soyoung, returns from a school trip with a mysterious, debilitating illness that doctors cannot explain.

Desperate to save her, Youngjun is introduced to a distant relative named Doyeon, who is a recluse living in a mountain cabin and is rumored to be a powerful shaman. Initially, Doyeon is cold and dismissive, refusing to help. However, as "ominous" spiritual events begin to escalate and shadow both men, they are forced to confront dark spirits and Doyeon’s own traumatic past.