I really enjoyed this.
The main character did have a certain humour about him - i laughed out loud several times throughout the episode. I really felt for him though when it showed the flashback of him reading the note pinned to the door, then opening the door (purely because of what had already been said about Red Johns drawing.
Also - at the end where he went home and just laid down on the mattress under Red Johns drawing. It's obviously an all-consuming need to bring him to justice.
I'll definitely be watching this throughout the series.......