Bad Guys, rated 8.8 on MDL - a lot of people wished there was a second season, it's quite a short drama (10 episodes, if I recall correctly) but it's definitely interesting and doesn't lack in well executed fighting scenes
The Man From Nowhere, rated 9 on MDL - it's a film starring Won Bin with some pretty dark themes (human trafficking, organ farming, etc)
Your profile says "Psychological stuffs (done right) are my weakness, anything with them would escalate the score"; I think both of these works fall under the Psychological theme, though Bad Guys perhaps focuses on it more than The Man From Nowhere