According to legend, those who lie during their lifetime will become "Feathered Ones" after death, condemned in the underworld to endure the endless torment of having their feathers plucked. One day, college student A-Tuo unexpectedly finds a black feather engraved with a name. That night, he witnesses the professor next door painfully pulling off his own fingers in his study. After the professor goes missing, A-Tuo discovers a feather growing from his own back—unraveling a terrifying secret that leads to the realm of the "Feathered Ones."