After having focused more on the victims' and culprits' characterization in the 20th century (exceptions do exist), writers of murder mysteries have, in the current times, been spending equal amount of time on the investigators as well. There are some very good examples in Broadchurch, Trapped, Shetland, Hinterland and of course Fargo the series which got inspiration from the movie of course. Marcella is one such attempt but they ended up creating a thoroughly unlikeable character due to her arrogance and judgemental nature. For me, it made the watching part a bit difficult and maybe at some point made me sympathize more with the culprits. Not sure it's bad writing but it is definitely one that can distance the audience a bit. I did somehow finish two seasons but the joker like scar and the invitation to work as under-cover was the point where I couldn't take it any more. Adios, Marcella.