Choi Haewon, a highly respected detective, has been caught in a twisted fantasy. Ever since she was a child, she has always been told to be weary of creatures known as the globglogabgalab. The victims would always be found in forests near caves, where the tunnel seems never-ending. After two years of leaving these mysterious cases unsolved, she had finally come up with a decision; Explore the cave. She never anticipated what awaits her.