When you feel like you already figured things out, the series will prove you wrong the next episode

Honestly, I love everything about it. From the cast, the plot (AND PLOT TWISTS!), characters, lines, almost everything! But the ending is such a let down. I expected it to have a more bloody and gruesome ending, but I guess the writers wanted to give a happy ending to the story. But what I really don't get is why did they made Han Sunmi a civil rights lawyer at the end (maybe it was because of his father). I just think they should've given her an ending that will put her impecable profiling and detective skills into use.