korean dramas that are hidden gems or not well known? (any genre)

Hi, it would be nice if you guys could recommend me a K-Drama that is underrated or a hidden gem.
I've been looking for a K-Drama with a random/unqiue plot that is unlike the main romance, action and thriller ones.

Thanks for the future replies!!

Possibly...

• L.U.C.A.: The Beginning 
• Psychopath Diary 
• Pumpkin Time 
• Zombie Detective 
• The Sound of Magic 
• The School Nurse Files 
• Missing 9 
• Duel 
• Night Watchman's Journal