Kang Seulgi is a brilliant junior NIS agent who's sworn to dedicate her life to stopping crime. But when a chilling case of mass murders puzzles the entire globe, Seulgi finds herself head to head with a mysterious force that may not even be from this world. As the number of victims increase with every passing day, she is left with no choice but to solve the most difficult case she's ever been tasked with—finding the true identi