K-Dramas like Psychopath Diary

6 shows with a similar feel

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  Mouse (2021)Also crime · mystery

  A psychopath's ruthless serial murders have left the entire nation gripped by fear and chaos. An honest, justice-seeking rookie police officer and a veteran detective with a tragic past, face off against the killer. After their encounter with the psychopath, their lives change completely.

  7 tracking it here
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  Busted! (2018)Also comedy · mystery

  Suspense, surprises and fun abound in this Korean variety game show featuring big personalities and even bigger mysteries in every episode.

  1 tracking it here
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  Nine Puzzles (2025)Also crime · mystery

  Ten years after discovering her murdered uncle, Ena and Detective Hansaem must cooperate to stop a series of similar murders - each linked by strange puzzle pieces.

  6 tracking it here
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  L.U.C.A.: The Beginning (2021)Also mystery · action & adventure

  Ji-O has a special power and a secret, but he doesn't know who he really is. He is chased by mysterious figures, while he tries to find answers to numerous questions that surround him. Goo-Reum is a detective. When she decides on a course of action, she won't change no matter what. Her parents disappeared when she was only a young child. Goo-Reum chases after the truth behind her parents' disappearance. She meets Ji-O and her life changes.
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  Flee For One's Life (2001)Also mystery · crime
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  Blood Lad (2013)Also comedy

  Staz is a vampire from the surreal "Demon World", and Fuyumi, an ordinary girl, accidentally wanders into the Demon World through a portal. Subsequently after meeting each other, Fuyumi is killed by a carnivorous plant and turned into a ghost, causing Staz to take responsibility and pledge to help bring her back to life.