At several crime scenes, humans are turning into demonic beings, and the main suspect caught on camera looks exactly like the male lead. The female lead carries an arrest warrant from the underworld and takes him into custody to stand before Heibai Wuchang for judgment. Desperate to clear his name, he blackmails her into helping him uncover what really happened. Their investigation brings a chilling conspiracy to light, along with a link between the killer and the male lead himself. Unknown to either of them, every step they take has been planned by a hidden mastermind. The result is a short supernatural mystery told across six episodes.