Hello Monster

Really hard to make a recommendation without spoilers...
Both:
-Have an in-depth mystery
-Focus on the mind/background of the serial murders and their influence
- Are mature and involve some deep thinking
- Touch the problem of being a child raised in an abusive/ 'murderer' family and get a bit in depth with it
- Can give you lifelong lessons if you listen carefully
- Do not use common and cheap drama moves, so its a bit refreshing
- Do not have a lot (to any) romance

(in both dramas)The murder of a family member in their youth causes one of the leads to pursue a career in law enforcement.... they end up working on a case that connects to their own family murder...